author: ZINTER, Justice. KONENKAMP, Justice

text:
    2002 SD 114
    STATE of South Dakota, Plaintiff and Appellee, v. William James BOLL, Defendant and Appellant.
    No. 22140.
    Supreme Court of South Dakota.
    Considered on Briefs May 28, 2002.
    Decided Sept. 4, 2002.

      Mark Barnett, Attorney General, Ann C. Meyer, Assistant Attorney General, Pierre, for plaintiff and appellee.
    John R. Hinrichs, Minnehaha County Public Defender, Sioux Falls, for defendant and appellant.
   ZINTER, Justice.

[¶ 1.] William James Boll was convicted of unauthorized manufacture of a controlled substance (methamphetamine) and possession of a controlled substance (methamphetamine) in violation of SDCL 22-42-2 and SDCL 22-42-5. He appeals contending that the trial court erred in denying his motion to suppress the evidence seized at his home and on his person. That evidence was seized pursuant to a search warrant. However, the affidavit supporting the warrant contained some information obtained from a prior illegal search. After redacting all information derived directly and indirectly from the illegal search, we conclude that the remaining information in the affidavit fails to establish probable cause. We therefore reverse and remand,

FACTS AND PROCEDURAL HISTORY

[¶ 2.] On December 13, 2000, the Sioux Falls Police Department received an anonymous letter from Casper, Wyoming. The author alleged that an individual, identified as “Cooley,” had been manufacturing methamphetamine in the basement of his home near Hartford, South Dakota. The letter also indicated that on November 29, 2000, the author told “a detective” that Cooley “deals marijuana.” The letter finally indicated that a woman and her children living in Cooley’s residence were in danger.

[¶ 3.] Sioux Falls Police Sergeant Jerry Mundt corroborated that “Cooley” was Boll. Boll’s criminal record indicated that Boll had used “Cooley” as an alias. Boll also lived at the address identified by the informant. Mundt was not, however, able to corroborate any other information in the letter.

[¶ 4.] The next day, December 14, Mundt and Minnehaha County Sheriffs Department Detective Tyron Albers drove to Boll’s rural farmhouse. The officers intended to investigate the allegations of the anonymous letter. The officers did not attempt to contact Boll before visiting his residence. They also did not obtain a search warrant. Instead, they intended to conduct what they described as a “knock and talk” with Boll when they arrived.

[¶ 5.] The officers drove to Boll’s residence, found Boll’s vehicle at home, but no one answered when the officers knocked on the front door. At this time Mundt made two observations. He first noticed that a gas grill near the front door had a missing propane tank. Mundt also observed footprints in the snow leading to a chicken coop within the curtilage of the house.

[¶ 6.] Instead of leaving upon making these discoveries, Mundt walked across the yard to the chicken coop. Although the door to that building was secured by a metal fence-post, Mundt removed the fence-post, opened the door, and looked inside.

[¶ 7.] Mundt immediately noticed evidence of an illegal methamphetamine laboratory. He first smelled a “strong odor of chemicals,” and he observed a “toluol container.” He also observed a propane tank that had a blue-green discoloration around the valve. Based upon his expertise in detecting clandestine drug labs, the discoloration indicated that anhydrous ammonia, a necessary component in the manufacture of methamphetamine, had been transported in the tank. The chemical odor and toluol container were also indicative of an illegal methamphetamine lab.

[¶ 8.] After making these observations, Mundt shut the door and replaced the fence-post that secured the door. He then advised Detective Albers, “well, I’m positive there is a meth lab here but unfortunately what I just did we can’t use to get a warrant.”

[¶ 9.] Five days later, on December 19, Mundt and Albers drove to Boll’s residence to investigate again. They were accompanied by Sioux Falls Police Detective Jim Severson. This time the officers did not immediately - approach the house. Instead, they parked on a hill about a half-mile away and observed Boll’s farmyard with binoculars. With the binoculars, Mundt could see that the door to the chicken coop was now open. Although Boll’s vehicle was not present, and although they had no search warrant, the officers then attempted to drive to Boll’s house. However, because Boll’s half-mile long driveway was blocked with snow, they walked through a cornfield to get to the residence.

[¶ 10.] When the officers reached the house, they knocked on the door, but no one answered. The officers then walked about 200 feet across Boll’s yard and inspected some “burn barrels” that were near the path they had used to approach the house. Mundt also walked to the now open door of the chicken coop and looked inside. He observed that the discolored propane tank was still present. Mundt and Severson then inspected the contents of the burn barrels and discovered two metal cans, one of which was labeled as toluol. They also found melted plastic that resembled pill containers. The officers left the premises without physically seizing this evidence.

[¶ 11.] Later that same day, Mundt prepared an. affidavit in support of a search warrant for Boll and his residence. In the affidavit, Mundt related the contents of the anonymous letter. Mundt also described his expertise in the investigation of clandestine methamphetamine labs and the methods used to manufacture methamphetamine. Mundt’s affidavit finally described the events and observations made at Boll’s residence. Paragraph' 3 described the observations -made on December 14, and paragraph 4 described the observations made on December 19. However, Mundt did not mention that he knew he had illegally entered on the first visit and could not use that illegally obtained information to get a search warrant. Mundt stated:

3. On 12-14-2000 Detective Tyrone Al-bers and I responded to 26150 466th Avenue to speak with Mr. Boll. A red [p]ick-up (sic) ..., registered to Mr. Boll, was parked next to the residence but no one answered the door. I did notice a gas grill, minus the propane tank, placed outside the only door to the residence and several outbuildings near the residence. I saw footprints leading up to the shed next to the house and, upon opening the door, smelled a strong odor of chemicals and a propane tank with blue-green discoloration around the valve. I resecured the door at that time and we left the farmplace.
4. On 12-19-2000 Detective Albers, Severson and I again responded to Bolls’ [sic] residence. The pick-up [sic] was gone and no one answered the door. The shed next to the house had the door standing open. While standing outside the shed I noticed ... (just as it was on 12-14-2000), a propane cylinder with a blue-green residue around the brass valve. I know from my training and experience that brass turns blue-green after it is exposed to anhydrous ammonia, a necessary element in the manufacture of methamphetamine using the “nazi” method. We also located a small burning barrel about 30 feet from this shed. The burned contents included[:] two square cans, one of which was to-luol, a common solvent used in the manufacture [of] methamphetamine and some sort of melted plastic which may have been old pill containers, like the ones used to store mini-thins (psue-doephedrine).

Mundt concluded that the items observed were indicative of an illegal methamphetamine lab at Boll’s residence.

[¶ 12.] Based upon this affidavit, a magistrate judge signed a search warrant for Boll’s home, vehicle, and person. The warrant was executed the next day, December 20, when Boll was not home. The officers found evidence consistent with the presence of a clandestine methamphetamine lab in Boll’s home. They later found a glass vial and a “pen tube” containing methamphetamine on Boll’s person.

[¶ 13.] Boll was subsequently. charged with one count of unauthorized manufacture of a controlled substance and one count of possession of a controlled substance. Prior to trial, Boll filed a motion to suppress the evidence seized from his person and at his residence. After a hearing, the motion was denied. A jury ultimately found Boll guilty of both charges. Boll now appeals from trial court’s denial of his motion to suppress.

STANDARD OF REVIEW

[¶ 14.] “A motion to suppress based on an alleged violation of a constitutionally protected right is a question of law reviewed de novo. We review findings of fact under the clearly erroneous standard. Once the facts have been determined, however, the application of a legal standard to those facts is a question of law reviewed de novo.” State v. Myhre, 2001 SD 109, ¶ 9, 633 N.W.2d 186, 188 (internal citations omitted).

DECISION

[¶ 15.] The trial court observed that there were three elements within the four corners of the affidavit that supported a probable cause determination: (1) the information about “Cooley” received in the anonymous letter from Wyoming, (2) the information in paragraph 3 which related the police officers’ observations made at Boll’s residence on December 14, and (3) the information in paragraph 4 which related the police officers’ subsequent observations made at Boll’s residence on December 19.

[¶ 16.] The trial court considered each element and concluded that standing alone, the anonymous letter did not establish probable cause. The trial court also concluded that the information obtained from the December 14 entry of the chicken coop could not be used to establish probable cause because it was the product of an illegal search. The trial court did, however, find that even in the absence of the illegal search, the police would have inevitably gone back to the premises because of the anonymous letter. Therefore, the trial court concluded that the information gathered from the December 19 visit could be used to support the search warrant because it was not based “exclusively” on the December 14 illegal search. Although the trial court was troubled by the December 14 illegal search, the court ultimately concluded that if the December 14 information were redacted from the affidavit, the remaining anonymous tip and observations of December 19 established probable cause for the warrant.

[¶ 17.] The trial court’s analysis involved application of two exceptions to the exclusionary rule: the inevitable discovery doctrine and a version of the independent source doctrine. Under the first exception, illegally seized evidence may be used if it would have been inevitably discovered by lawful means. Under the second exception, a search warrant that is partially based upon tainted evidence and partially based on evidence arising from an independent source need not be invalidated if the lawfully obtained evidence establishes probable cause apart from the tainted information. People v. Weiss, 20 Cal.4th 1073, 86 Cal.Rptr.2d 337, 978 P.2d 1257 (1999); State v. Revenaugh, 133 Idaho 774, 992 P.2d 769 (1999); United States v. Herrold, 962 F.2d 1131 (3dCir.1992); United States v. Restrepo, 966 F.2d 964 (5thCir.1992). See also State v. Wagoner, 130 N.M. 274, 24 P.3d 306, 311 (Ct.App.2001).

[¶ 18.] We now review the exclusionary rule and these exceptions. We then consider whether the December 19 observations and the evidence seized under the search warrant may be used under those exceptions as well as under the good faith exception to the exclusionary rule.

[¶ 19.] Generally, “[t]he exclusionary rule prohibits introduction into evidence of tangible materials seized during an unlawful search, and of testimony concerning knowledge acquired during an unlawful search.” Murray v. United States, 487 U.S. 533, 536, 108 S.Ct. 2529, 2533, 101 L.Ed.2d 472 at 480 (1988). It also “prohibits the introduction of derivative evidence, both tangible and testimonial, that is the product of the primary evidence, or that is otherwise acquired as an indirect result of the-, unlawful search, up to the point at which the connection with the unlawful search becomes ‘so attenuated as to dissipate the taint.’ ” Id. at 536-37, 108 S.Ct. at 2533, 101 L.Ed.2d at 480 (citing Nardone v. United States, 308 U.S. 338, 341, 60 S.Ct. 266, 268, 84 L.Ed. 307, 312 (1939)). The purpose of the exclusionary rule is to deter police misconduct. State v. Belmontes, 2000 SD 115, ¶ 13, 615 N.W.2d 634, 638.

The Inevitable Discovery Exception to the Exclusionary Rule

[¶ 20.] The inevitable discovery doctrine, also known as the hypothetical independent source doctrine, is an exception to the exclusionary rule. Under this exception, “illegally obtained evidence may be admitted if the evidence ultimately would have been discovered by legitimate means.” State v. Shearer, 1996 SD 52, ¶ 21, 548 N.W.2d 792, 796-97 (citing Nix v. Williams, 467 U.S. 431, 444, 104 S.Ct. 2501, 2509, 81 L.Ed.2d 377, 387-88 (1984)). “The inevitable discovery doctrine ... is in reality an extrapolation from the independent source doctrine: Since the tainted evidence would be admissible if in fact discovered through an independent source, it should be admissible if it inevitably would have been discovered.” Murray, 487 U.S. at 539, 108 S.Ct. at 2534, 101 L.Ed.2d at 481-82 (emphasis in original). See also Wagoner, 24 P.3d at 311.

[¶ 21.] The inevitable discovery doctrine does, however, have limited application. Wagoner succinctly pointed out that the inevitable discovery is hypothetical in nature and therefore, it does not apply if the alternative, legitimate source is actually used to seize the evidence.

The inevitable discovery doctrine applies where evidence may have been seized illegally, but where an alternative legal means of discovery, such as a routine police inventory search, would inevitably have led to the same result. For the doctrine to apply, the alternate source of evidence must be pending, but not yet realized. If the alternate source has been realized, and the evidence seized or “reseized” according to this alternate source, the inevitable discovery doctrine is no longer applicable. Instead, the admissibility of the evidence must be evaluated under the independent source doctrine.

Wagoner, 24 P.3d at 311 (emphasis added).

[¶ 22.] In this case, the inevitable discovery doctrine does not apply because the search warrant and the December 19 observations were not hypothetical events. Both events occurred and were used to seize (or reseize) the incriminating evidence at issue. Because the. inevitable discovery doctrine is inapplicable in cases like this where the hypothetical, alternate source has been realized, we next consider whether the December 19 observations and the fruits of the search warrant could be used under the independent source doctrine.

The Independent Source Exception to the Exclusionary Rule

[¶ 23.] The independent source doctrine applies when evidence is legally seized through a source independent of an illegal search. The exception was first recognized by the United States Supreme Court in Silverthorne Lumber Co. v. United States, 251 U.S. 385, 40 S.Ct. 182, 64 L.Ed. 319 (1920), overruled on other grounds by United States v. Havens, 446 U.S. 620, 100 S.Ct. 1912, 64 L.Ed.2d 559 (1980). The Silverthome Court held that although the exclusionary rule forbids any use of illegally seized evidence, “[i]f knowledge of [the evidence] is gained from an independent source [it] may be proved like any [other]....” 251 U.S. at 392, 40 S.Ct. at 183, 64 L.Ed. at 321.

[¶ 24.] The Supreme Court considered the independent source doctrine again in Segura v. United States, 468 U.S. 796, 104 S.Ct. 3380, 82 L.Ed.2d 599 (1984). In Segura, the defendants were arrested in their apartment for drug trafficking. After the arrest, the officers conducted an illegal warrantless sweep of the defendants’ apartment and observed drug paraphernalia. The purpose of the sweep was to secure the apartment while the officers waited for a warrant to conduct a full search. Although the sweep was illegal, no information obtained during the sweep was used to procure the warrant. 468 U.S. at 814, 104 S.Ct. at 3390, 82 L.Ed.2d at 614. Under those circumstances, the Supreme Court held that the. evidence obtained pursuant to the valid warrant was admissible as an independent source. 468 U.S. at 816, 104 S.Ct. at 3391, 82 L.Ed.2d at 616.

[¶ 25.] In reaching its holding, the Court emphasized the independent nature of the evidence:

None of the information on which the warrant was secured was derived from or related in any way to the initial entry into petitioners’ apartment; the information . came from sources wholly unconnected with the entry and was known to the agents well before the initial entry. No information obtained during the initial entry or occupation of the apartment was needed or used by the agents to secure the warrant. It is therefore beyond dispute that the information possessed by the agents before they entered the apartment constituted an independent source for the discovery and seizure of the evidence now challenged.

468 U.S. at 814, 104 S.Ct. at 3390, 82 L.Ed.2d at 614-15 (emphasis added).

[¶ 26.] Later, in Murray, the United States Supreme Court identified two circumstances where a search warrant will not qualify as an independent source. The Court specifically cautioned :that a warrant would not qualify as an independent source “if the agents’ decision to seek the warrant was prompted by what they had seen during the initial entry, or if information obtained during that entry was presented to the Magistrate and affected his decision to issue the warrant.” Murray, 487 U.S. at 542, 108 S.Ct. at 2536, 101 L.Ed.2d at 483-484 (emphasis added). Both of these disqualifying circumstances prevent the use of the December 19 observations and the fruits of the search warrant in Boll’s case.

[¶ 27.] The use of the December 19 information is prohibited by the first Murray disqualification because the illegal search of Boll’s property on December 14 partially prompted the officers’ observations on December 19, which further prompted the decision to obtain a search warrant. We acknowledge that Mundt testified, and the trial court found, that Mundt would have continued to investigate the matter because of the letter alone. However, the officers’ return and look into the coop on December 19, and the resulting decision to get the warrant, were prompted at least in part by the illegal search on December 14.

[¶ 28.] The officers’ conduct. compels that conclusion. On December 19, the officers returned , to the residence after Mundt’s illegal December 14 search and resulting declaration: “well I’m positive this is a meth lab here but unfortunately what I just did we can’t use to. get a warrant.” Although they did not stop and use binoculars on December 14, they did so on December 19. The officers immediately noted that the chicken coop door was now open. This fact, and the, subsequent re-entry of the coop, were important to the officers only because they exploited the information'they obtained from the initial, illegal observations in the coop on December 14.

[¶ 29.] Moreover, on December 19 they observed that Boll’s vehicle was not present and the half-mile long driveway was blocked with snow. Nevertheless, they proceeded to the home to purportedly talk with Boll. When they confirmed that he was not at home, they then walked through the snow and looked again into the chicken coop. Although the door to the chicken coop was now Open making the interior arguably subject to plain view, the plain view exception to the warrant requirement was unavailable because the December 19 view revealed the same evidence observed during the prior illegal entry on December 14. See State v. Corder, 460 N.W.2d 733, 737 (S.D.1990) (stating “[p]lain view requires that the evidence be discovered inadvertently, in other words, that the officers did not know in advance the location of the evi-denee”)(citing Texas v. Brown, 460 U.S. 730, 103 S.Ct. 1535, 75 L.Ed.2d 502 (1983)).

[¶ 30.] In addition to the officers’ conduct, Mundt admitted that their return on December 19 was partly prompted by the December 14 illegal search. At the suppression hearing, Mundt testified:

Question: Is it fair to say that a good portion of the reason you went back [to Boll’s residence] on the 19 is because of suspicious activity you observed when you were there on the 14?
Answer: Well, we were still trying to follow upon the letter thing, looking for suspicious activity, yes. Correct.
Question: Were you following up on’the fact you saw the canister in there, too?
Answer: We were still following up on the case I guess, yes.
Question: That obviously cemented your earlier suspicions?
Answer: It made me feel this was the kind of lab that we were looking at; that we were looking at an ephedrine reduction method lab, yes.

This testimony clearly indicated that the police decision to return on December 19 (which ultimately led to the search warrant) was prompted in part by the illegal search.

[¶ 31.] This conclusion is finally supported by the trial court’s findings. After conducting the suppression hearing, the trial court did not find that the December 19 investigation was wholly independent of the December 14 observations. On the contrary, the trial court only found that the December 19 visit was not based “exclusively on the illegal act that occurred on December 14.” The inescapable inference is that although the officers’ visit on the 14th may not have been the exclusive reason for their return, the illegal search remained at least a part of the reason for the December 19 return. As the trial court noted, “once the police'saw what was in the shed [on the 14th] there was no question in heaven or earth that they were going to go out there again.”

[¶ 32.] The exclusionary rule prohibits this type of derivative evidence that is the indirect product or fruit of illegal police conduct. Wong Sun v. United States, 371 U.S. 471, 83 S.Ct. 407, 9 L.Ed.2d 441 (1963). Evidence is not “ ‘fruit of the poisonous tree’ simply because it would not have come to light but for the illegal actions of the police.” The question is “whether, granting establishment of the primary illegality, the evidence to which instant objection is made has been come at by exploitation of that illegality or instead by means sufficiently distinguishable to be purged of the primary taint.” 371 U.S. at 488, 83 S.Ct. at 417, 9 L.Ed.2d at 455 (internal citations omitted). Because the December 19 observations (and the subsequent search warrant) were obtained by partially exploiting the illegal December 14 search, the primary taint was not purged. Moreover, because the December 19 observations were partially prompted by what was observed during the illegal observation, the first Murray disqualification is present, and the independent source doctrine is not available.

[¶ 33.] The independent source doctrine is also unavailable because of the second Murray disqualification. Under that disqualification, “if information obtained during [the illegal] entry was presented to the Magistrate and affected his decision to issue the warrant,” the independent source rule does not apply. Murray, 487 U.S. at 542, 108 S.Ct. at 2536, 101 L.Ed.2d at 483. Here, both the illegal December 14 observations and the tainted December 19 observations were included in the affidavit that was presented to the magistrate judge. Because that information clearly affected the magistrate’s decision to issue the warrant, the independent source doctrine is also inapplicable under the second Murray disqualification.

The Expanded Independent Source Doctrine

[¶ 34.] Notwithstanding these Murray disqualifications, several state and federal courts have expanded the independent source doctrine to allow partially tainted warrants if the remaining untainted information establishes probable cause. See, e.g., Weiss, 86 Cal.Rptr.2d 337, 978 P.2d at 1263; Revenaugh, 992 P.2d at 774-75; Herrold, 962 F.2d at 1141-42; Restrepo, 966 F.2d at 970. Generally, courts have adopted this expansion of the independent source doctrine because they were unwilling to put the police in a position worse than they would have been in had they not acted illegally. See Herrold, 962 F.2d at 1141.

[¶ 35.] Under the expansion, the question is whether “the remaining information presented to the magistrate, after the tainted evidence is excluded, contains adequate facts from which the magistrate could have concluded that probable' cause existed for the issuance of the search warrant.” Revenaugh, 992 P.2d at 774 (additional citations omitted). See also Weiss, 86 Cal.Rptr.2d 337, 978 P.2d at 1263 (stating “if the [affidavit] contains probable cause apart from the improper information, then the warrant is lawful and the independent source doctrine applies ... ”).

[¶ 36.] However, this affidavit fails even under that expansion. As the California Supreme Court noted in Weiss, “the officers [may not be] prompted to obtain the warrant by what they observed during the initial entry.” Id. (citing Restrepo, 966 F.2d at 970). Here, the police were partially prompted to return and obtain a warrant because of what they observed on December 14. Therefore, the expanded independent source doctrine cannot save the evidence from the exclusionary rule because the observations from both visits must be redacted, and the remaining anonymous letter fails to establish probable cause.

The Good Faith Exception To The Exclusionary Rule

[¶ 37.] The State finally argues that we should apply the good faith exception to the exclusionary rule. The good faith exception was adopted by the United States Supreme Court in United States v. Leon, 468 U.S. 897, 104 S.Ct. 3405, 82 L.Ed.2d 677 (1984). The Leon court explained:

The deterrent purpose of the exclusionary rule necessarily assumes that the police have engaged in willful, or at the very least negligent, conduct which has deprived the defendant of some right. By refusing to admit evidence gained as a result of such conduct, the courts hope to instill in those particular investigating officers, or in their future counterparts, a greater degree of care toward the rights of an accused. Where the official action was pursued in complete good faith,' however, the deterrence rationale loses much of its force.

Leon, 468 U.S. at 919, 104 S.Ct. at 3418, 82 L.Ed.2d at 696 (emphasis added). We adopted the good faith .exception in State v. Saiz, 427 N.W.2d 825, 828 (S.D.1988) (stating “evidence is admissible when police officers reasonably rely on a warrant that is subsequently invalidated because a judge finds there was an insufficient basis for the issuing magistrate to find probable cause”) (emphasis added).

[¶ 38.] To qualify for the good faith exception, the offending officer must have “acted in the objectively reasonable belief that [his] conduct did not violate the Fourth Amendment.” Leon, 468 U.S. at 918, 104 S.Ct. at 3418, 82 L.Ed.2d at 696; Belmontes, 2000 SD 115 at ¶ 14, 615 N.W.2d at 638 (stating “[t]his good faith inquiry is limited to the ‘objectively ascertainable question of whether a reasonable well trained officer would have known that the search was illegal despite the magistrate’s authorization’ ”) (citing State v. Klosterman, 114 Ohio App.3d 327, 683 N.E.2d 100, 103 (1996)).

[¶ 39.] Here, Mundt did not have an objectively reasonable belief that his illegal search on December 14, or his use of that search in the affidavit, was in compliance with the Fourth Amendment. Mundt admitted at the time of the December 14 search that he knew his entry of the chicken coop was illegal and could not be used for a search warrant. Nevertheless, he knowingly included the illegally obtained information in the affidavit. The good faith exception does not apply.

[¶ 40.] Reversed and remanded for further proceedings consistent with this opinion.

[¶ 41.] GILBERTSON, Chief Justice, and SABERS and AMUNDSON, Justices, concur.

[¶ 42.] KONENKAMP, Justice, concurs specially.

KONENKAMP, Justice

(concurring specially).

[¶ 43.] I concur with the Court’s opinion. I write specially to identify the structure of the tests to be used and the standards of review to be employed in deciding whether the independent source exception to the exclusionary rule should apply when an illegal search preceded a warranted search. The test has three elements, each of which must be addressed: (1) the warrant affidavit, purged of any information gained through the initial, illegal search, must contain sufficient facts to constitute probable cause for the issuance of the warrant; (2) the decision to seek the warrant must not have been prompted by what was seen during the initial, illegal search; and (3) any information obtained during the illegal search and presented to the issuing judge must not have affected the decision to issue the warrant. See generally Murray v. United States, 487 U.S. 533, 108 S.Ct. 2529, 101 L.Ed.2d 472 (1988); United States v. Restrepo, 966 F.2d 964, 966 (5th Cir.1992).

[¶ 44.] Although the first element invokes a legal question, our review is ordinarily highly deferential. Illinois v. Gates, 462 U.S. 213, 236, 103 S.Ct. 2317, 2331, 76 L.Ed.2d 527 (1983). In the usual case, we review challenges to the sufficiency of a warrant by looking at the totality of the circumstances to decide if there was at least a “substantial basis” for the issuing judge’s finding of probable cause. Id. at 238-39, 103 S.Ct. at 2332 (citations omitted). Our inquiry is whether the information provided to the judge was sufficient for a “common sense” decision that there was a “fair probability” the evidence would be found on the person or at the place to be searched. Id. Furthermore, we review the issuing judge’s probable cause decision to grant a search warrant independently of the conclusion reached by the suppression hearing court. State v. Jackson, 2000 SD 113, ¶ 8, 616 N.W.2d 412, 416 (citations omitted). “[I]n a doubtful or marginal case a search under a warrant may be sustainable where without one it would fall.” See United States v. Ventresca, 380 U.S. 102, 106, 85 S.Ct. 741, 744, 13 L.Ed.2d 684 (1965). However, in a case like this one, involving an illegal prior search, the deferential, substantial basis standard of review is inapplicable when the issuing judge never considered the warrant affidavit purged of the tainted information. Restrepo, 966 F.2d at 971 n. 18.

[¶ 45.] The second element — inquiring whether information gained in the illegal search prompted the officers to seek a warrant — raises a factual question, discerned from the subjective intent of the officers. Motivation must be inferred from the totality of the facts and circumstances. The Restrepo decision provides useful guidance for making this determination: “the [trial] court might wish to consider such items as the precise nature of the information acquired during the illegal search ... [and] the relative probative import of this information compared to all other information known to the officers .... ” 966 F.2d at 972. The question is the “actual motivation or intention of the officers in the particular case,” a subjective rather than an objective test. Wayne R. LaFave, 5 Search & Seizure § 11.4(f) at 300 (3d ed.1996).

[¶ 46.] Here, the circuit court did not specifically address the subjective question whether the decision to seek the warrant was prompted by what was seen during the initial, illegal entry. Murray, 487 U.S. at 542, 108 S.Ct. at 2536 (emphasis added). Were the police so prompted, or not? If the court were convinced that the officers were so prompted, the results of the second, warranted search would be inadmissible. Since the court did not explicitly answer this question, we would ordinarily remand for further findings. See Restrepo, 966 F.2d at 972; U.S. v. Bosse, 898 F.2d 113, 116 (9thCir.1990) (remanding to determine effect of illegal entry and search on the officers’ decision to seek warrant). In a similar case, the North Dakota Supreme Court likewise remanded to the trial court the question of motivation. See State v. Winkler, 552 N.W.2d 347, 354 (N.D.1996). As the United States Supreme Court said in Murray, “it is the function of the [trial court], rather than the [appeals court], to determine the facts[J” 487 U.S. at 543, 108 S.Ct. at 2536. In this unique instance, however, the trial court’s findings obliquely disposed of this question, though not the way the trial court intended.

[¶ 47.] On the third element, the question is not whether any illegally obtained information actually affected the decision of the particular judge who issued the warrant; the question is whether the information presented, with the illegally obtained material excised, was objectively sufficient to establish probable cause. See Restrepo, 966 F.2d at 969-70. As the Third Circuit explained in U.S. v. Herrold,

the Court’s use of “affect” in Murray must be understood to signify affect in a substantive manner. Thus, the fact that an application for a warrant contains information obtained through an unlawful entry does not per force indicate that the improper information “affected” the [issuing judge’s] decision to issue the warrant and thereby vitiate the applicability of the independent source doctrine. Rather, if the application contains probable cause apart from the improper information, then the warrant is lawful and the independent source doctrine applies, providing that the officers were not prompted to obtain the warrant by what they observed during the initial entry.

962 F.2d 1131, 1141-42 (3rd Cir.1992). Thus, in cases where the tainted information is contained in the warrant affidavit, the first and third elements coincide.

[¶ 48.] Lastly, on the' question of exigent circumstances, the trial court found that safety concerns about the explosive and toxic dangers of chemicals used to manufacture methamphetamine were not sufficient reasons to justify Sergeant Mundt’s decision to open the shed door and look inside. This was a question of law. State v. Sleep, 1999 SD 19, ¶ 6, 590 N.W.2d 235, 237. The ruling was not appealed. Nonetheless, it is important to point out for future decisions that safety factors are a valid consideration in determining whether exigent circumstances exist. See Mincey v. Arizona, 437 U.S. 385, 392-93, 98 S.Ct. 2408, 2413, 57 L.Ed.2d 290 (1978); Michigan v. Tyler, 436 U.S. 499, 509-10, 98 S.Ct. 1942, 1950, 56 L.Ed.2d 486 (1978). The Eighth Circuit recently emphasized that the “potential hazards of methamphetamine manufacture are well documented, and numerous cases have upheld limited warrantless searches by police officers who had probable cause to believe they had uncovered an on-going methamphetamine manufacturing operation.” United States v. Walsh, 299 F.3d 729, 734 (8th Cir.2002) (citations omitted).

      . SDCL 22-42-2 provides that it is a Class 4 felony for any person 'to "manufacture, distribute or dispense a substance listed in Schedules I or.II....” Methamphetamine is a Schedule II substance. SDCL 34-20B-16.
      SDCL 22-42-5 provides that it is a Class 4 felony for any person to "knowingly possess a controlled drug or substance unless the substance was obtained directly or pursuant to a valid prescription or order from a practitioner ... or except as otherwise authorized by chapter 34-20B.”

      . At trial the officers excluded any reference to the illegal observations gleaned from their December 14 visit to Boll's residence (paragraph 3 of the affidavit).

      . The State did not file a notice of review on this ruling.

      . The State did not file a notice of review on this ruling.

      . The trial court relied on United States v. Williams, 633 F.2d 742 (8th Cir.1980).

      . We also note that “for inevitable discovery to apply, the lawful means by which the evidence could have been attained must be wholly independent of the illegal actions.” Wagoner, 24 P.3d at 311 (emphasis added).

      . Other courts have not expanded the doctrine. See Wagoner, 24 P.3d at 315; State v. Lewis, 809 P.2d 925, 930 (Alaska Ct.App.1991); Commonwealth v. Melendez, 544 Pa. 323, 676 A.2d 226, 231 (1996); State v. Clark, 844 S.W.2d 597, 600 (Tenn.1992).

      . This "citizen tip” was even more deficient than the one that failed to establish the lower standard of "reasonable suspicion” in Graf v. Dep't of Commerce & Regulation, 508 N.W.2d 1, 3-4 (S.D.1993). There, we held that an anonymous tip which only provided the license number of the vehicle, the general location of the vehicle, and advised that the driver might "possibly” be drunk, did not establish reasonable suspicion.


source: Caselaw Access Project

author: ANDERSON, RUSSELL A., Justice. STRINGER, J.

license: Public Domain

text:
    R. Austin CHAPMAN and Nadine Chapman, Relators, v. COMMISSIONER OF REVENUE, Respondent.
    No. C5-02-245.
    Supreme Court of Minnesota.
    Aug. 29, 2002.
    Rehearing Denied Oct. 14, 2002.

      Mike Hatch, Attorney General, Barry R. Greller, Assistant Attorney General, St. Paul, MN, for Relator’s.

      Sue Ann Nelson, Gary Hanson, Martin A. Culhane III, Robert J. Stewart, Oppenheimer Wolff & Donnelly LLP, Minneapolis, MN, for Respondent.
   OPINION

ANDERSON, RUSSELL A., Justice.

Individual taxpayers subject to the Minnesota alternative minimum tax (AMT) are permitted a charitable contribution deduction if the contribution is made “to or for the use of’ a charitable organization “located in and carrying on substantially all of its activities in the [State of Minnesota].” Minn.Stat. §§ 290.091, subd. 2(f), and 290.21, subd. 3(b) (1994). In this case, we are asked to determine whether rela-tors’ contributions to a Massachusetts donor-advised charitable gift fund qualified for deduction under Minnesota’s AMT provisions and, if not, whether Minnesota’s AMT provisions violate the Commerce Clause and Equal Protection Clause of the United States Constitution and the Uniformity Clause of the Minnesota Constitution. The Minnesota Tax Court determined that relators’ contributions did not qualify for deduction because they were neither made to qualifying Minnesota charities nor made in trust for qualifying Minnesota charities. The tax court also determined that Minnesota’s AMT provisions allowing a deduction for contributions to Minnesota charities but not for contributions to non-Minnesota charities do not violate the Commerce Clause, the Equal Protection Clause, or the Uniformity Clause. We affirm in part and reverse in part.

In 1992, R. Austin Chapman and Nadine Chapman, relators, established a donor-advised fund account with the Fidelity Investments Charitable Gift Fund in Boston, Massachusetts. In 1994, 1995, and 1996, the Chapmans made contributions to this fund. In computing their Minnesota AMT liabilities for each of these three years, the Chapmans deducted the amount of their contribution to the fund for that year.

The respondent Commissioner of Revenue subsequently disallowed these deductions on the grounds that the Fidelity fund was not located in Minnesota and did not carry on substantially all of its activity in Minnesota. The Commissioner assessed additional tax liability and interest against .the Chapmans for the relevant' tax years of $145,006.34. After the Commissioner’s decision was upheld on administrative appeal, the Chapmans challenged the decision in the Minnesota Tax Court. The Chapmans argued that their contributions to the Fidelity fund were made “for the use of’ Minnesota charities within the meaning of Minn.Stat. §§ 290.091, subd. 2(f) and 290.21, subd. 3(b). They also argued that restriction of the Minnesota AMT charitable deduction to Minnesota charities violates the Commerce Clause and the Equal Protection Clause of the U.S. Constitution and violates the Uniformity Clause of the Minnesota Constitution. The Chapmans sought reversal of the additional taxes and interest assessed by the Commissioner.

The parties then stipulated to the facts and sought summary judgment from the tax court. The parties stipulated that (1) the Fidelity Charitable Gift Fund is a trust formed in Massachusetts and a public charity under the Internal Revenue Code of 1986, (2) contributions made to this fund from 1994 through 1996 were deductible under the Code and under Minn.Stat. § 290.01, subd. 19 (2000), (3) Fidelity’s principal office is in Massachusetts, (4) the Chapmans contributed $313,200 to the fund in 1994, $462,100 to the fund in 1995, and $838,000 to the fund in 1996, (5) no distributions from the fund were made to any charity from 1994 through 1996, (6) from 1997 through 2000, distributions from the fund were made to various charitable organizations and foundations by Fidelity as designated by the Chapmans, (7) Fidelity complied with every distribution request or grant recommendation made by the Chapmans, (8) in 1997, all but $20,000 of the $377,500 distributed by Fidelity went to charitable organizations and foundations located in Minnesota, (9) from 1998 through 2000, all of the funds distributed by Fidelity went to charitable organizations and foundations located in Minnesota, and (10) in calculating their Minnesota AMT liability for the tax years 1994 through 1996, the Chapmans reported contributions made to Fidelity in each of the years as qualified “Minnesota charitable contribution deductions” under Minn.Stat. § 290.091, subd. 2(f).

The tax court denied the Chapmans’ motion for summary judgment and granted the Commissioner summary judgment. The court explained that under Minnesota’s AMT provisions, individual taxpayers are permitted a charitable contribution deduction if the contribution is made “to or for the use of’ qualifying charitable organizations. Drawing on federal tax cases, the court concluded that the term “for the use of’ under-the Minnesota AMT provisions means “irrevocably in trust for.” Because the Chapmans did not make charitable contributions “irrevocably in trust for” Minnesota charitable, organizations, they did not qualify for the AMT deduction.

The tax court also held that Minnesota’s AMT charitable contribution provisions do not violate the U.S. and Minnesota Constitutions. The court explained that the provisions implicate the Commerce Clause because donations to donor-advised conduit funds constitute economic activity in the stream of commerce. However, the court decided that the limited scope of the charitable contribution deduction does not violate the Commerce Clause because the denial does not discriminate against interstate commerce. More specifically, the court reasoned that the- statute allows a deduction for contributions to conduit funds located both in Minnesota and outside Minnesota so long as the contributions made to the conduit funds are made “for the use of’ Minnesota charities. Finally, the court determined that Minnesota’s AMT charitable contribution provisions do. not violate the Equal Protection Clause or the Uniformity Clause because those AMT provisions do not discriminate against the use of conduit funds located outside Minnesota.

Following the tax court decision, the Chapmans filed a petition for writ of cer-tiorari asking our court to evaluate whether the tax court erred in interpreting Minnesota’s AMT statutory scheme and whether the AMT statutory scheme violates the U.S. Constitution or the Minnesota Constitution.

I.

Our review of tax court decisions is limited to determining whether the tax court lacked jurisdiction, whether the tax court’s decision is supported by the evidence and is in conformity with the law, and whether the tax court committed any other error of law. Skyline Preservation Found. v. County of Polk, 621 N.W.2d 727, 731 (Minn.2001); Minn.Stat. § 271.10, subd. 1 (2000). We review an order granting summary judgment to determine whether there are any genuine issues of material fact and whether the lower court erred in applying the law. Burlington N.R.R. v. Comm’r of Revenue, 606 N.W.2d 54, 57 (Minn.2000). Because the parties stipulated to the facts underlying this dispute, we need only consider whether the applicable law was properly applied. We review de novo the tax court’s conclusions of law, including the interpretation of statutes. Id. Because states have wide latitude in establishing their taxation schemes, and because statutes are declared unconstitutional only when absolutely necessary, a taxpayer challenging the constitutionality of a state tax statute bears a heavy burden. Stelzner v. Comm’r of Revenue, 621 N.W.2d 736, 740 (Minn.2001). We will uphold a statute unless the challenging party demonstrates that it is unconstitutional beyond a reasonable doubt. Olson v. Ford Motor Co., 558 N.W.2d 491, 496 (Minn.1997).

The first question before us is whether the tax court properly construed the challenged provisions to find that the charitable contribution deduction for the AMT must be made to or in trust for Minnesota charitable organizations. To address this question, it is necessary to examine the Minnesota AMT statutory scheme.

The computation of an individual taxpayer’s Minnesota AMT liability begins with calculation of the taxpayer’s Minnesota alternative minimum taxable income (AMTI). Minn.Stat. § 290.091, subd. 1(a) (2000). The Minnesota AMTI is determined by making various adjustments required by Minn.Stat. § 290.091, subd. 2(a), to the taxpayer’s federal AMTI. These adjustments include an “add-back” of itemized deductions permitted for federal AMTI purposes, meaning that the amounts of those deductions remain taxable income for Minnesota AMT purposes. Minn.Stat. § 290.091, subd. 2(a). The statute includes two exceptions to this dis-allowance of federal itemized deductions— one for the “Minnesota charitable contribution deduction” and the other for the medical expense deduction. Minn.Stat. § 290.091, subd. 2(a)(2). This statutory structure results in the disallowance of deductions for all charitable contributions in computing the Minnesota AMTI except the “Minnesota charitable contribution deduction.” It is that differential treatment that is at issue here.

The “Minnesota charitable contribution deduction” is defined for purposes of the Minnesota AMT as “a charitable contribution deduction under section 170 of the Internal Revenue Code to or for the use of an entity described in section 290.21, subdivision 3, clauses (a) to (e).” Minn.Stat. § 290.091, subd. 2(f). Section 290.21, subdivision 3 sets forth, as relevant here, certain allowable deductions for contributions or gifts made in the taxable year, including amounts contributed within the taxable year:

(b) to or for the use of any community chest, corporation, organization, trust, fund, association, or foundation located in and carrying on substantially all of its activities within this state, organized and operating exclusively for religious, charitable, public cemetery, scientific, literary, artistic, or educational purposes, or for the prevention of cruelty to children or animals no part of the net earnings of which inures to the benefit of any private stockholder or individual.

Minn.Stat. § 290.21, subd. 3(b) (emphasis added).

Based on the above provisions, charitable contributions are deductible for purposes of the Minnesota AMT only if made “to or for the use of’ a Minnesota charitable organization or foundation. In contrast to contributions “to” a charitable organization, contributions “for the use of’ logically refers to the forms other than direct contributions. Minnesota’s AMT provisions do not define the term “for the use of,” and we have not interpreted this term. Therefore, its meaning must be determined through statutory construction.

“The object of all interpretation and construction of laws is to ascertain and effectuate the intention of the legislature.” Minn.Stat. § 645.16 (2000). “When the words of a law in their application to an existing situation are clear and free from all ambiguity, the letter of the law shall not be disregarded under the pretext of pursuing the spirit.” Id. In construing the meaning and scope of a statute, the words of the statute govern and are given their common and approved usage. Northern States Power Co. v. Comm’r of Revenue, 571 N.W.2d 573, 575 (Minn.1997). In ascertaining the intent of the legislature, we are guided by the presumption that the legislature does not intend to violate the U.S. Constitution and that the legislature does not intend a result that is absurd, impossible to execute, or unreasonable. Minn.Stat. § 645.17 (2000).

Although we have not had the opportunity to interpret the phrase “for the use of,” federal courts have construed this term in the context of charitable contribution deductions under federal tax statutes. These courts have addressed the forms that charitable contributions may take to qualify for a deduction and have uniformly concluded that the term “for the use of’ means “in trust for.” In Davis v. United States, 495 U.S. 472, 479-84, 110 S.Ct. 2014, 109 L.Ed.2d 457 (1990), the U.S. Supreme Court held that the transfer of funds did not qualify as a charitable contribution made “for the use of’ a charitable organization within the meaning of 26 U.S.C. § 170 (1982) in the absence of evidence that the funds were transferred “in trust for” the charitable organization. The Court concluded that this interpretation of the term “for the use of’ was consistent with congressional intent and the purpose of the statute as a whole, which was to provide tax benefits to charitable organizations. Davis, 495 U.S. at 483-84, 110 S.Ct. 2014. The Court reasoned that requiring contributions to be made in trust or in some similar legal arrangement would foster charitable giving because the beneficiary would have the legal power and incentive to insure that donated funds were used for the designated charitable purposes. Id. Before the Supreme Court decision in Davis, several lower federal courts had similarly construed “for the use of’ to mean “in trust for.” See Orr v. United States, 343 F.2d 553 (5th Cir.1965); Rockefeller v. Comm’r of Internal Revenue, 76 T.C. 178, 1981 WL 11372 (1981); Appleby v. C.I.R., 48 T.C. 330, 1967 WL 944 (1967); O’Brien v. C.I.R., 46 T.C. 583, 1966 WL 1188 (1966).

The federal courts’ longstanding construction that the term “for the use of’ means “in trust for” in the context of charitable contribution deductions is persuasive in interpreting our own AMT provisions. In addition, the more flexible meaning of “for the use of’ that the Chap-mans advocate would, as the tax court explained, create significant administrative burdens for the Commissioner in enforcing the statute. For example, the Chapmans did not designate a beneficiary at the time they made their contributions to the Fidelity fund in 1994 through 1996, and none of those contributions were distributed until at least 1997. The practical difficulties in auditing and enforcing a “for the use of’ requirement against undirected contributions that may in the future be used for Minnesota charities are obvious and not likely intended by the legislature. For these reasons, we conclude that the tax court properly construed the term “for the use of’ to mean “in trust for.” Because the Chapmans did not make their charitable contributions “to” or “in trust for” Minnesota charitable organizations, we affirm the tax court’s ruling that the Chap-mans’ contributions fail to qualify for the Minnesota AMT deduction.

II.

Because the Chapman’s contributions do not qualify for the AMT deduction, we must address their argument that the statute so construed is unconstitutional. We first address their challenge under the Commerce Clause.

The Commerce Clause provides that “[t]he Congress shall have the Power * * * to regulate Commerce with foreign Nations and among the several states.” U.S. Const, art. I, § 8, cl. 3. Although the Commerce Clause represents an affirmative grant of power to Congress, it has long been held to impliedly contain a negative command, commonly referred to as the “dormant” Commerce Clause, that the states may not discriminate against or unduly burden interstate commerce. Quill Corp. v. North Dakota, 504 U.S. 298, 312, 112 S.Ct. 1904, 119 L.Ed.2d 91 (1992).

Commerce Clause challenges involve a two-step inquiry. Stelzner v. Comm’r of Revenue, 621 N.W.2d 736, 740 (Minn.2001). We first determine whether the challenged statute implicates the Commerce Clause and, if it does, then evaluate whether the statute violates the Commerce Clause. Id.

“It is well settléd that actions are within the domain of the Commerce Clause if they burden interstate commerce or impede its free flow.” C & A Carbone, Inc. v. Clarkstown, 511 U.S. 383, 389, 114 S.Ct. 1677, 128 L.Ed.2d 399 (1994). There are three broad categories of activity that fall under the purview of the Commerce Clause: (1) the use of the channels of interstate commerce, (2) the instrumentalities of interstate commerce, or persons or things in interstate commerce, and (3) activities having a substantial effect on interstate commerce. United States v. Lopez, 514 U.S. 549, 558-59, 115 S.Ct. 1624, 131 L.Ed.2d 626 (1995). Thus, to show that Minnesota’s AMT -charitable contribution provisions implicate the Commerce Clause, the Chapmans must demonstrate that those provisions concern (1) the use of the channels of interstate commerce, (2) the instrumentalities of interstate commerce, or the persons or things in interstate commerce, or (3) activities having a substantial effect on an interstate activity or market. See United States v. Faasse, 265 F.3d 475 (6th Cir.2001) (discussing whether a challenged law regulates the use of the channels of interstate commerce or things in interstate commerce); Luther v. Comm’r of Revenue, 588 N.W.2d 502, 510 (Minn.1999) (discussing whether a challenged tax has a substantial effect on interstate commerce).

Here, Minnesota’s AMT provisions establish a charitable deduction for contributions “to or for the use of’ any charitable organization “located in and carrying on substantially all of its activities within this state.” Minn.Stat. § 290.21, subd. 3(b). Payments are things in interstate commerce and payments to parties across state' lines require the- use of the channels of interstate commerce. Faasse, 265 F.3d at 489-90. The activities of nonprofit charitable organizations fall within the protection of the dormant Commerce Clause. Camps Newfound Owatonna, Inc. v. Town of Harrison, 520 U.S. 564, 586, 117 S.Ct. 1590, 137 L.Ed.2d 852 (1997). Thus, paying and making donations to charitable organizations across state lines concern things in interstate commerce and the channels of interstate commerce. In addition, the AMT charitable contribution provisions substantially affect interstate commerce because the nonprofit organizations they support constitute & substantial sector of the economy and interstate commerce. Id. For these reasons,' we conclude that Minnesota’s AMT charitable contribution - provisions implicate the Commerce Clause.

The Commissioner contends that the AMT charitable contribution provisions do not implicate, the Commerce Clause because (1) they apply to a relatively small number of taxpayers and (2) the deduction directly implicates only the personal tax liability of individuals residing in Minnesota or otherwise subject to the Minnesota tax and does not have a direct impact on any interstate business or market. However, the Commissioner’s first argument fails because for purposes of a discrimination claim under the Commerce Clause the magnitude and scope of the discrimination against interstate commerce have no bearing on the question of whether the Commerce Clause has been violated. See Camps Newfound, 520 U.S. at 581 n. 15, 117 S.Ct. 1590. In other words, there is no' de minimis defense to this type of Commerce Clause challenge. Id. The Commissioner’s second argument is also unavailing. Although it is true that the Commerce Clause protects markets and participants in markets rather than taxpayers as such, General Motors Corp. v. Tracy, 519 U.S. 278, 300, 117 S.Ct. 811, 136 L.Ed.2d 761 (1997), a state regulation imposed on individual taxpayers that does not directly tax a commercial activity or organization can implicate the Commerce Clause. Id. at 580, 117 S.Ct. 1590. Accordingly, we are not persuaded by the Commissioner’s arguments that the AMT provisions do not implicate the Commerce Clause.

Because the AMT provisions implicate the Commerce Clause, we must next determine whether these provisions violate the Commerce Clause. In Complete Auto Transit v. Brady, 430 U.S. 274, 97 S.Ct. 1076, 51 L.Ed.2d 326 (1977), the U.S. Supreme Court adopted a four-part test to determine whether a state’s tax system violates the Commerce Clause. To withstand constitutional scrutiny, a state tax must (1) be applied to an activity with a substantial nexus with the taxing state, (2) be fairly apportioned, (3) not discriminate against interstate commerce, and (4) be fairly related to the services provided by the state. Complete Auto, 430 U.S. at 279, 97 S.Ct. 1076. If any of these criteria are not met, the statute violates the Commerce Clause. Id.

The Chapmans focus on the third prong of the Complete Auto test and contend that Minnesota’s AMT charitable contribution provisions discriminate against interstate commerce. The dormant Commerce Clause invalidates state measures that “unjustifiably * ⅜ ⅜ discriminate against or burden the interstate flow of articles of commerce.” Oregon Waste Sys., Inc. v. Dept. of Envtl. Quality, 511 U.S. 93, 98, 114 S.Ct. 1345, 128 L.Ed.2d 13 (1994). The term “discrimination” in the dormant Commerce Clause context means differential treatment of instate and out-of-state economic interests that benefits the former and burdens the latter. Oregon Waste, 511 U.S. at 99, 114 S.Ct. 1345. Statutes that are facially discriminatory are “virtually per se invalid.” Id. However, a state may defend the law “under the per se rule by demonstrating that it ‘advances a legitimate local purpose that cannot be adequately served by reasonable nondiscriminatory alternatives.’ ” Camps Newfound, 520 U.S. at 581, 117 S.Ct. 1590 (citations omitted). “This is an extremely difficult burden, ‘so heavy that facial discrimination by itself may be a fatal defect.’ ” Id. at 582, 117 S.Ct. 1590 (citations omitted). “Once a state tax is found to discriminate against out-of-state commerce, it is typically struck down without further inquiry.” Chemical Waste Management, Inc. v. Hunt, 504 U.S. 334, 342, 112 S.Ct. 2009, 119 L.Ed.2d 121 (1992).

Here, the challenged AMT provisions allow a deduction for contributions “to or for the use of’ any charitable organization “located in and carrying on substantially all of its activities within this state,” Minn.Stat. § 290.21, subd. 3(b), but no deduction is allowed for charitable contributions to non-Minnesota charities. Minn.Stat. § 290.091, subd. 2. On its face, the statute treats contributions to in-state charitable organizations differently from contributions to out-of-state charitable organizations. The activities of nonprofit charitable organizations fall within the protection of the dormant Commerce Clause. Camps Newfound, 520 U.S. at 586, 117 S.Ct. 1590. Because this statute is facially discriminatory, it is per se invalid unless the state demonstrates that the statute “ ‘advances a legitimate local purpose that cannot be adequately served by reasonable nondiscriminatory alternatives.’ ” Oregon Waste, 511 U.S. at 101, 114 S.Ct. 1345 (citations omitted). Because the Commissioner has not defended Minnesota’s AMT charitable contribution provisions under the per se rule, we decline to address the question of whether there is a legitimate local purpose that cannot be adequately served by reasonable nondiseriminatory alternatives. Camps Newfound, 520 U.S. at 582-83 n. 16, 117 S.Ct. 1590 (stating that a court should not address a possible defense under the per se rule if not raised by the state).

The Commissioner argues that despite its facial discrimination, the AMT charitable contribution provisions do not violate the Commerce Clause because their purpose is to provide AMT taxpayers with an incentive to contribute to charities that assist the state in discharging some of its core public functions. According to the Commissioner, the Commerce Clause is not offended when a state statute directly assists the state in fulfilling its core function of ensuring the health and welfare of its citizens, rather than implementing some form of economic protectionism. However, the Supreme Court rejected this very argument in Camps Newfound. In that case, the town argued that because the challenged exemption statute was designed to lessen the state’s social services burden and to foster the societal benefits provided by charitable organizations, it should be treated the same as an expenditure of government funds for the same purposes. 520 U.S. at 588-89, 117 S.Ct. 1590. The Court explained that even assuming that a direct subsidy benefiting only those nonprofits serving principally Maine residents would be permissible, “our cases do not sanction a tax exemption serving similar ends.” Id. at 589, 117 S.Ct. 1590. Accordingly, the Commissioner’s argument that the AMT provisions encourage contributions to nonprofit institutions that may “relieve the state of some of its welfare burden” does not save the charitable contribution provisions from constitutional infirmity under the Commerce Clause.

Because the AMT charitable contribution provisions facially discriminate against interstate commerce by allowing a deduction for contributions to only Minnesota charities, the statute violates the Commerce Clause. Inasmuch as we conclude that the AMT charitable contribution provisions violate the Commerce Clause, we need not determine whether they violate the Equal Protection Clause of the U.S. Constitution or the Uniformity Clause of the Minnesota Constitution.

III.

Having concluded that Minnesota’s AMT charitable contribution provisions unconstitutionally discriminate against interstate commerce, we must determine the consequences for the statutory scheme. Specifically, the question is whether the exclusion from the charitable deduction add-back for Minnesota contributions should be severed, resulting in no deductions for charitable contributions in calculating the AMTI, or whether other language can be severed such that deductions for contributions to all charitable organizations are authorized, regardless of whether the charity is located in Minnesota or elsewhere. The Chapmans ask us to choose the latter course. The Commissioner urges us to remand the case to the tax court to determine how severance ought to be crafted to comport with legislative intent.

The legislature has provided guidance on how a ruling of partial invalidity of a statute should be implemented. Minn. Stat. § 645.20 (2000). Section 645.20 establishes a general rule of severability, under which a court must sever any unconstitutional provisions from a statute and leave the remaining provisions intact, unless the legislature has specified that the statute’s provisions are not severable or it is apparent that the legislature would not have enacted the remaining provisions without those that are to be severed. Section 645.20 provides:

Unless there is a provision in the law that the provisions shall not be severa-ble, the provisions of all laws shall be severable. If any provision of a law is found to be unconstitutional and void, the remaining provisions of the law shall remain valid, unless the court finds the valid provisions of the law are so essentially and inseparably connected with, and so dependent upon, the void provisions that the court cannot presume the legislature would have enacted the remaining valid provisions without the void one; or unless the court finds the remaining valid provisions, standing alone, are incomplete and are incapable of being executed in accordance with the legislative intent.

Id.

When a court determines that a statute is unconstitutional, it must invalidate as much of the statute as is necessary to eliminate the unconstitutionality. Archer Daniels Midland Co. v. State, 315 N.W.2d 597, 600 (Minn.1982). We look first to the intent of the legislature to fashion a remedy consistent with that intent. Id. While we can strike a severable statutory provision if found to be unconstitutional and void, “we cannot add language to a statute in order to render it constitutionally permissible.” McGuire v. C & L Restaurant Inc., 346 N.W.2d 605, 614 (Minn.1984); Thompson v. Estate of Petroff, 319 N.W.2d 400, 407 (Minn.1982).

Because the 1994 AMT statute does not provide that its provisions are not severable, we apply the principles of section 645.20 to the statute. Under section 290.091, the Minnesota alternative minimum taxable income is defined as the sum of several items for the taxable year, including:

[t]he taxpayer’s itemized deductions allowed in computing federal alternative minimum taxable income, but excluding the Minnesota charitable contribution deduction and the medical expense deduction.

Minn.Stat. § 290.091, subd. 2(a)(2) (1994). In practical terms, the unconstitutional discrimination of allowing a deduction for Minnesota charitable contributions but not for others can be cured either by making all charitable contributions deductible or by making none deductible. The Chap-mans seek a curative interpretation of the AMT charitable contribution provisions that would permit them to deduct contributions to charitable organizations regardless of whether the charity is located in Minnesota. However, the Chapmans do not explain how the governing severance principles can achieve such a result. Nor do they identify particular offending language that could be severed from the statute to eliminate the add-back of all charitable deductions.

We conclude that the result sought by the Chapmans is not possible under our severance rules given the manner in which the statute is written. The statute establishes the general rule that the taxpayer’s itemized deductions allowed in computing their federal AMTI must be added back in calculating their Minnesota AMTI. The statute creates an exception to this general rule, however, by excluding the Minnesota charitable contribution deduction from the add-back of itemized deductions. It is this exclusion of only the Minnesota charitable contribution deduction that offends the Commerce Clause. Because this exception to the general rule is the source of the constitutional infirmity of the statute, the language establishing the exception is the language that must be severed. Accordingly, to eliminate the source of the constitutional problem with the AMT provisions, we sever the language “the Minnesota charitable contribution deduction” from section 290.091, subd. 2(a)(2). The result is that under the statute, the Minnesota AMTI consists of, among other things, the itemized deductions allowed in computing the federal AMTI, including deductions for contributions to Minnesota charities and non-Minnesota charities as well.

The Chapmans argue that severance principles should be used to eliminate the unconstitutional discrimination by instead allowing all charitable contributions. They claim this result is necessary to preserve the legislature’s intent to allow a deduction for contributions to Minnesota charities. Obviously, in enacting the AMT charitable contribution provisions the legislature did intend to allow a deduction for contributions to Minnesota charities. But just as obviously, the legislature intended not to allow a deduction for contributions to non-Minnesota charities and to include charitable contributions to non-Minnesota charities in calculating Minnesota AMT. That intent is expressed in the general rule of adding back federal itemized deductions, with limited specified exceptions. However, as we have concluded both aspects of the legislature’s intent cannot be effectuated without violating the Commerce Clause, and therefore we must determine, using severance principles set out by the legislature, which option the legislature would have chosen if it had known it could not do both.

The evolution of the AMT charitable contribution provisions provides some insight that is helpful in making this determination. That evolution reveals that the legislature has never allowed deductions from the AMT for all charitable contributions, yet it has in the past disallowed deductions for contributions to Minnesota charities. Although the 1994 version of subdivision 2(a)(2) provides that the Minnesota charitable contribution deduction is excluded in computing the AMTI, this was not always the case. In 1986, no charitable contribution deduction could be excluded in computing the AMTI. Minn. Stat. § 290.091 (1986). In 1987, the legislature altered the definition of the AMTI to include an exclusion for “the portion of the charitable contribution deduction that constitutes an item of tax preference under section 57(a)(6) of the Internal Revenue Code.” See Minn.Stat. § 290.091, subd. 2 (Supp.1987). Section 57(a)(6) provided for an appreciated property charitable deduction, defined as “[t]he amount by which the deduction allowable under section 170 or 642(c) would be reduced if all capital gain property were taken into account at its adjusted basis.” 26 U.S.C. § 57(a)(6) (1987). Although this amendment allowed a deduction from the AMTI for some charitable contributions, it was limited to the narrow category of appreciated property contributions.

In 1990, the AMT statute was amended to provide that in computing the AMTI the taxpayer could exclude from the add-back the “Minnesota charitable contribution deduction.” See Minn.Stat. § 290.091, subd. 2 (1990). The 1990 amendment also defined the Minnesota charitable contribution deduction as “a charitable contribution deduction under section 170 of the Internal Revenue Code to or for the use of an entity described in section 290.021, subdivision 3, clauses (a) to (e).” Id. The following year the legislature amended section 290.091, subdivision 2 again, providing that in computing the AMTI, there was an exclusion from the add-back for the “Minnesota charitable contribution deduction and non-Minnesota charitable deductions to the extent they are included in federal alternative minimum taxable income under section 57(a)(6) of the Internal Revenue Code.” See Minn.Stat. § 290.091, subd. 2 (Supp.1991). The effect of this amendment was to reinstate the deduction for appreciated property charitable contributions that was the subject of the 1987 amendment, particularly as applicable to non-Minnesota contributions. In 1994, the legislature again amended section 290.091, subd. 2, to provide an exclusion from the add-back for the “Minnesota charitable contribution deduction” in computing the AMTI. Minn.Stat. § 290.091, subd. 2 (1994). This version of the Minnesota charitable contribution add-back exclusion eliminated the favorable treatment for non-Minnesota contributions of appreciated property that had been reinstated in 1991.

This history of Minnesota’s AMT charitable contribution provisions illustrates that while the legislature has vacillated in its treatment of contributions to charities in calculating the AMTI, it has never permitted an exclusion from the add-back for all charitable contribution deductions, as the Chapmans advocate. Significantly, when previous versions of the AMT law did provide an exclusion from the add-back for contributions to non-Minnesota charities, that exclusion was limited to the appreciated property charitable deduction as defined by section 57(a)(6) of the Internal Revenue Code. Moreover, in 1994 the legislature deleted even that limited exclusion for non-Minnesota charitable contribution deductions. Thus, the legislature’s treatment of charitable deductions in the AMT law over the years demonstrates more consistently its intent to disallow deductions for contributions to non-Minnesota charities than its intent to allow deductions for Minnesota charities. There is no suggestion in its current or past treatment of charitable contributions under the AMT that the legislature would choose to allow deductions for all charitable contributions. On the other hand, the alternative of disallowing all charitable contributions for AMT purposes was the law in 1986.

Therefore, we cannot discern from this legislative history any indication that the legislature would choose to allow deductions for all charitable contributions if its preference for a deduction only for Minnesota contributions were invalid. Therefore, the intent of the legislature would be frustrated even if the unconstitutional language of the AMT provisions could be severed to provide an exclusion from the add-back for all charitable contribution deductions. We therefore conclude that under the principles of section 645.20, the language of section 290.091, subd. 2(a) that excludes “the Minnesota charitable contribution deduction” must be severed from the remaining valid provisions. The result is that deductions for all charitable contributions are among the itemized deductions that must be added back in computing the Minnesota AMTI; that is, there is no deduction for any charitable contributions for Minnesota AMTI purposes.

TV.

Although we have concluded that the unconstitutionality of the AMT charitable contribution provisions will be cured by severing the language that provides favorable treatment for contributions to Minnesota charities, the question remains whether this curative interpretation of the statute should be applied prospectively only, or whether it can be applied retroactively to defeat the Chapman’s claim that the Commissioner’s assessment of additional tax liability for tax years 1994-1996 should be vacated. The Chapmans argue that having established the invalidity of the Minnesota-only charitable contribution deduction, they are entitled to “meaningful backward-looking relief’ under McKesson Corp. v. Division of Alcoholic Beverages & Tobacco, 496 U.S. 18, 31, 110 S.Ct. 2238, 110 L.Ed.2d 17 (1990), that would allow them to exclude from the add-back what the courts have determined to be their non-Minnesota charitable contribution deduction. The Chapmans contend, without further explanation, that this “is the. only remedy that preserves legislative intent, * * * is fair and administratively feasible, and adopts the same rules as applicable for regular tax purposes.” The Commissioner contends, also without explanation, that the Chapmans are not entitled to meaningful backward-looking relief under McKesson.

In McKesson, the Supreme Court addressed whether Florida could, consistent with due process, provide only prospective relief where a taxpayer had paid liquor taxes under a law held to violate the Commerce Clause by discriminating in favor of Florida products. The Court held that the “State [must] provide meaningful backward-looking relief to rectify any unconstitutional deprivation.” McKesson, 496 U.S. at 31, 110 S.Ct. 2238. The Court explained that the Due Process Clause of the Fourteenth Amendment required that the state provide a backwards-looking remedy whereby those who had paid the tax were put in the same position as those who had been favored by the unlawful exemption. Id. at 43, 110 S.Ct. 2238. We similarly conclude that due process requires the Commissioner to provide meaningful backward-looking relief to the Chapmans.

The question remains what shape that relief must take. In McKesson the requirement of backward-looking relief did not necessarily mandate a refund of taxes paid. Rather, the Court held that there were three types of backward-looking remedies that a state could employ to rectify the unconstitutional discrimination. Id. at 40-41, 110 S.Ct. 2238. First, it could refund the difference between the tax paid by the victim of the discrimination and the tax that would have been assessed had the taxpayer been granted the unlawful exemption. Id. Second, to the extent consistent with other constitutional restrictions and state law, it could assess and collect taxes from those favored by the unlawful discrimination to put them on equal footing with those who had been discriminated against. Id. Third, it could apply a combination of a partial refund and a partial retroactive assessment. Id. These three options were available because the tax law was not invalid per se, but only because it discriminated against interstate commerce. Therefore, the Due Process Clause demanded only a remedy that insured that “the resultant tax actually assessed during the contested tax period reflects a scheme that does not discriminate against interstate commerce.” McKesson, 496 U.S. at 41, 110 S.Ct. 2238; see also Fulton Corp. v. Faulkner, 516 U.S. 325, 346-47, 116 S.Ct. 848, 133 L.Ed.2d 796 (1996).

In McKesson and subsequent cases presenting similar remedy issues, the Supreme Court has not dictated a remedy from among the McKesson alternatives, but has instead remanded to the state courts to determine the appropriate remedy. E.g., McKesson, 496 U.S. at 51, 110 S.Ct. 2238; Fulton Corp., 516 U.S. at 347, 116 S.Ct. 848. Some state courts confronted with cases in which the McKesson remedial alternatives are available have left the selection of a remedy from among those alternatives to the taxing authority. See, e.g., PPG Industries, Inc. v. Com., Bd. of Fin. and Revenue, 567 Pa. 580, 790 A.2d 261, 270 (2001) (explaining McKesson alternatives and directing Commonwealth to provide a retrospective remedy consistent with opinion); Fulton Corp. v. Faulkner, 345 N.C. 419, 481 S.E.2d 8, 11 (1997) (holding that state legislature should determine whether to cure discriminatory tax by enforcing tax as to all or forgiving tax in its entirety); Matter of Hawaiian Flour Mills, Inc., 76 Hawai’i 1, 868 P.2d 419, 426-27 (1994) (holding that Director of Taxation may select remedial option). Other courts have held that the refund option must be implemented because retroactive taxation is not a viable alternative. See Cendian Corp. v. Franchise Tax Bd., 85 Cal.App.4th 875, 102 Cal.Rptr.2d 611, 621 (2000) (requiring refund because state statute of limitation on tax assessment bars retroactive tax collection alternative); Scottsdale Princess Partnership v. Dept. of Revenue, 191 Ariz. 499, 958 P.2d 15, 21 (App.1997) (rejecting retroactive taxation option because of due process concerns and unwillingness of taxing authority to use it).

In this case, the tax court had no occasion to address the remedy issue because it held the AMT charitable contribution provisions do not violate the Commerce Clause. As noted, the Chapmans argue that the meaningful backward-looking relief to which they are entitled should be allowance of a deduction for their non-Minnesota contributions, but this position appears to be premised primarily on their severance argument. They offer no significant assessment of the McKesson alternatives. The Commissioner does not address the McKesson alternatives, arguing instead that remedy issues are not ripe without a remand for the tax court to assess the severance issue.

We have resolved the severance issue and with it the issue of prospective- application of the AMT charitable contribution provisions. We have also determined that meaningful backward-looking relief must be provided to the Chapmans. In the absence of adequate briefing by the parties, we decline to direct which of the McKesson options must be employed to achieve that relief.

Remand to the tax court will allow the parties to address this issue of which McKesson alternative should be retrospective remedy here. Nonetheless, we note our concern regarding the option of retroactive imposition of tax liability in the circumstances of this case. While the Court in McKesson listed retroactive taxation of the taxpayers previously advantaged by the discriminatory tax as one of the possible options to cure the Commerce Clause violation, it pointed out that due process does impose some limitation on the availability of that option. Id. at 40 n. 23, 110 S.Ct. 2238 (noting that “the retroactive assessment of a tax increase does not necessarily deny due process to those whose taxes are increased, though beyond some temporal point the retroactive imposition of a significant tax burden may be ‘so harsh and oppressive as to transgress the constitutional limitation’ ”); see United States v. Carlton, 512 U.S. 26, 114 S.Ct. 2018, 129 L.Ed.2d 22 (1994) (explaining due process standard applicable to retroactive taxation). The availability of the retroactive taxation remedy may also be limited by state law, such as the statute of limitations on assessment of back taxes. See Ceridian Corp., 102 Cal.Rptr.2d at 621 (requiring refund because state statute of limitation on tax assessment bars retroactive tax collection alternative).

Advised by the parties, the tax court can fully assess the effect of these or any other limitations on the application of the McKesson remedial options to the Chapman’s claim. We remand to the tax court to determine which of the McKesson alternatives is the proper remedy in the circumstances of this case.

Affirmed in part, reversed in part and remanded.

GILBERT, J., took no part in the consideration or decision of this case.

MEYER, J., not having been a member of this court at the time of argument and submission, took no part in the consideration or decision of this case.

STRINGER, J.

Concurring in part, dissenting in part.

I agree with the conclusion of the majority that Minnesota’s alternative minimum tax provision allowing a tax deduction for charitable contributions to charitable organizations “located in and carrying on substantially all of its activities within this state,” but denying deductions to non-Minnesota charities, discriminates against interstate commerce and therefore violates the Commerce Clause of the United States Constitution. In doing so, we reverse the tax court, but because the tax court held the law constitutional, it went no further in its analysis. Thus the concept of severance of the unconstitutional provision of the statute and the remedy were not addressed by the tax court, and were neither briefed nor argued to this court. I therefore dissent from the court’s ruling on those issues, as I think it is inappropriate for the court to address them in the absence of a record and briefing from the parties.

Relators offer no substantive suggestion as to how severance can be achieved and make only a passing reference to the remedy, and the Commissioner recommends that if this court rules the law unconstitutional, the matter be remanded to the tax court to determine what the legislature might have done had it known it could not constitutionally deny the deduction for contribution to out-of-state charities and at the same time allow it for in-state charities. I agree with the Commissioner’s recommendation.

The majority relies heavily on the statutory principle of severance set forth in Minn.Stat. § 645.20:

Unless there is a provision in the law that the provisions shall not be severa-ble, the provisions of all laws shall be severable. If any provision of a law is found to be unconstitutional and void, the remaining provisions of the law shall remain valid, unless the court finds the valid provisions of the law are so essentially and inseparably connected with, and so dependent upon the void provisions that the court cannot presume the legislature would have enacted the remaining valid provisions without the void one; or unless the court finds the remaining valid provisions, standing alone, are incomplete and are incapable of being executed in accordance with the legislative intent.

Id.

Based on this principle of severance, the majority concludes that the only way to render constitutional Minnesota’s disallowance of the deductibility of contributions to non-Minnesota charities, while allowing contributions to Minnesota charities, is to strike Minn.Stat. § 290.091, subd. 2(a)(2)(1994), the provision permitting the deduction of contributions to in-state charities. By doing so, the majority rules, the playing field is leveled because all contributions, whether to in-state charities or out-of-state charities, are denied. The majority bases its severance remedy on a review of the legislative history of the alternative Minnesota tax provision, pointing out that it shifted from time to time, but historically seemed to favor a concept of disallowance of the charitable contribution. The fallacy of this analysis however, is that at best it relates to the legislative attitude toward allowance or disallowance over a broad span in history and is no value at all in arriving at a presumption as to whether the legislature enacting the current version of section 290.091, subd. 2(a)(2) in 1994 “would have enacted the remaining valid provisions without the void one.” I see no basis for the conclusion of the majority, and on a matter of great importance relating to tax policy, the tax court should hold an evidentiary hearing to permit the parties to produce evidence as to what tax policy actually drove the legislation — the general rule of permitting deductions for all charitable contributions, or a special rule for AMT taxpayers denying the deduction. In the absence of a record on the issue, the court could well have reached a result opposite from the conclusion reached by the majority.

My further concern is that while the majority raises the question whether the curative interpretation of the statute should be applied prospectively only, it does not resolve the question. And while it rules that the relators are entitled to “backward looking relief’ under McKesson Corp. v. Division of Alcoholic Beverages & Tobacco, 496 U.S. 18, 110 S.Ct. 2238, 110 L.Ed.2d 17 (1990), it seems to ignore the fact that in ruling that the offending provision of the statute is the allowance of deduction to in-state charities, and that this must be severed, there is “no backward looking relief’ available to relators. They can’t be allowed the deduction for their out-of-state contribution because the provision of the statute prohibiting allowance remains intact; and the obverse— disallowing their deductions for their instate contribution — would surely be the most perverse of all “backward looking relief.” Relators may have won the battle but they would surely have lost the war.

This conundrum seems wholly unnecessary. A remand to the tax court to fashion a severance under Minn.Stat. § 645.20 consistent with the court’s unconstitutionality ruling will set the parameters for a remedy that does provide relators relief.

      . The federal alternative minimum tax was enacted to reduce the opportunity for individuals with high income to achieve minimal income tax liability through use of exclusions, deductions and credits provided in federal tax law. See Michael D. Rose and John C. Chom-mie, Federal Income Taxation § 3.38 (3d ed.1988). The Minnesota alternative minimum tax appears intended to serve the same purpose, as it is patterned on, though not identical to, the federal law.

      . The tax court does not have original jurisdiction to decide constitutional issues. Erie Mining Co. v. Comm’r of Revenue, 343 N.W.2d 261, 264 (Minn.1984). The tax court acquires jurisdiction to decide all issues in a particular case, including constitutional issues, when the district court transfers the case to the tax court. In re McCannel, 301 N.W.2d 910, 919-20 (Minn.1980). In order to insure that the tax court would have jurisdiction to decide the constitutional issues, the Chapmans and the Commissioner filed a joint motion to refer the constitutional issues to the district court and to transfer those issues back to the tax court. The tax court issued an order of referral and a stay of proceedings and the district court issued an order transferring the case back to the tax court.

      . For the tax years at issue, the statute provided, in relevant part:
      (a) "Alternative minimum taxable income” means the sum of the following for the taxable year:
      (1) the taxpayer's federal alternative minimum taxable income * * *;
      (2) the taxpayer’s itemized deductions allowed in computing the federal alternative minimum taxable income, but excluding the Minnesota charitable contribution deduction and the medical expense deduction;* * * *.
      Minn.Stat. § 290.091, subd. 2(a) (1994).

      . Because the Minnesota AMT provisions refer specifically to certain federal tax provisions and because the Minnesota AMT provisions are based on federal income tax law, we may refer to federal law for guidance in interpreting the term “for the use of.” See Steele County Bldg. & Loan Ass’n v. Comm’r of Taxation, 263 Minn. 176, 116 N.W.2d 506, 511 (1962).

      . The Supreme Court has found per se invalidity was overcome on this basis in only one case. See Maine v. Taylor, 477 U.S. 131, 141, 106 S.Ct. 2440, 91 L.Ed.2d 110 (1986). In that case, the Court found that the state had no reasonable nondiscriminatory alternatives to the action it had taken. Oregon Waste, 511 U.S. at 101, 114 S.Ct. 1345 (discussing the holding in Maine v. Taylor).

      . This prospective interpretation of the statute is, of course, subject to legislative modification, consistent with the limitations of the dormant Commerce Clause and other relevant constitutional provisions.

      . In its discussion of due process requirements in McKesson, the Court indicated that the issue of meaningful backward-looking relief might not be present if the taxpayer had a genuine opportunity for predeprivation relief. Id. at 38-39, 110 S.Ct. 2238. See also Cambridge State Bank v. James, 514 N.W.2d 565, 569-71 (Minn.1994) (holding refund of discriminatory tax required because predeprivation remedy not clearly available for tax years at issue). The Chapmans not only had, but availed themselves of, a predeprivation opportunity to challenge the AMT law without paying the challenged taxes. Therefore, the issue here, is not whether the Chapmans are entitled to a refund, but whether the additional tax liability assessed by the Commissioner remains valid. We find no authority and discern no principle under which this difference in circumstances from McKesson and Cambridge State Bank lessens the state’s obligation to provide a meaningful remedy to the Chap-mans that eliminates the unlawful discrimination against interstate commerce for the contested tax period.

      . Contrary to the implication by the dissent, our severance determination concerning the prospective application of the statute does not limit the available options for backward-looking relief.

      . In reaching this conclusion, the majority notes that relators failed to explain how they get to their conclusion that all contributions should be exempt from the AMT, or to explain how severance of the statute could be fashioned to reach that result. This is not surprising, as the Commissioner notes, because the issue was not before the tax court, there was no record of any kind and neither the Commissioner nor relators addressed it to this court.