dissenting.
The three petitioners in this case all have criminal records that include two or more misdemeanor convictions for simple possession of an illegal drug. None has a felony conviction. The distinction between felony convictions and misdemeanor convictions is critical to non-citizens who are subject to removal from this country. (It is also of great import to those being considered for certain sentencing enhancements under the Sentencing Guidelines, but this is a topic for another time.) Ordinarily persons subject to removal may petition the United States Attorney General and ask that he use his discretion to cancel a removal order. 8 U.S.C. § 1229b(a). The Attorney General, however, has no discretion to cancel the removal of a person who has been convicted of an aggravated felony. 8 U.S.C. § 1229b(a)(3). The battle over what constitutes an aggravated felony, therefore, recurs with some frequency and fervor in immigration cases. The answer may mean the difference between the possibility of staying in this country or leaving behind family, children, and the homes the petitioners may have known their whole lives. Florencio Victor Manuel Jimenez-Mateo has lived in this country for approximately forty-two of his fifty-six years. He has been a lawful permanent resident since 1971. If deported, he will be leaving behind his job, his two United States citizen children and the country he has called home since his early teens. Julio Cesar Calderon has lived in this country for twenty of his twenty-eight years. He has two United States citizen children who reside here. Omar Cende-jas-Fernandez is twenty-five years old and has lived in this country legally since 1992. They have each been convicted of two (and in one case three) misdemeanor crimes. Whether the law requires us to consider these men’s multiple convictions for misdemeanor drug crimes as felonies for purposes of removal proceedings is critical to them, as it will be to many others.
The answer lies buried in a maze of cross-referenced immigration and criminal statutes. Because the majority has expertly set forth each of the statutes, I need only trace through them in a cursory fashion. The Immigration and Nationality Act (INA) defines “aggravated felony” with a list of crimes that includes drug trafficking. 8 U.S.C. § 1101(a)(43)(B). It also notes that “[t]he term [aggravated felony] applies to an offense described in this paragraph whether in violation of state or federal law.” Id. at § 1101(a)(43). The INA then points readers to the criminal code (specifically 18 U.S.C. § 924(c)) for a definition of a drug trafficking crime. *875That section of the criminal code, in turn, defines a drug trafficking crime as “any felony punishable under the Controlled Substances Act.” 18 U.S.C. § 924(c)(2). And finally, the Controlled Substances Act (CSA) turns a second-time drug conviction into a felony if the government files the necessary information with the court and serves it upon the defendant. 21 U.S.C. § 844, § 851. If this convoluted path has made the weary reader’s eyes glaze over, they must come into focus here, for the petitioners win or lose based on how the Supreme Court, instructs the lower courts to decide whether a particular state crime falls within the rubric of the CSA. The Supreme Court, in Lopez v. Gonzales, 549 U.S. 47, 127 S.Ct. 625, 633, 166 L.Ed.2d 462 (2006), declared that a state drug offense is analogous to a felony punishable under the Controlled Substances Act “only if it proscribes conduct punishable as a felony under that federal law.” Id.
Some courts, including our own, have described the Supreme Court’s approach in Lopez as the “hypothetical federal felony approach.” See, e.g., Escobar Barraza v. Mukasey, 519 F.3d 388, 390 (7th Cir.2008); U.S. v. Pacheco-Diaz, 513 F.3d 776, 779 (7th Cir.2008) (“Pacheco-Diaz II”); see also Rashid v. Mukasey, 531 F.3d 438, 443 (6th Cir.2008); In re Carchuri-Rosendo, 24 I & N Dec. 382, 396 (BIA 2007) (Pauley, J., concurring). In following the hypothetical federal felony approach, we look to see whether a defendant’s conviction would have been a felony if the defendant had been prosecuted under federal law. Lopez, 127 S.Ct. at 632-33; Gonzales-Gomez v. Achim, 441 F.3d 532, 535 (7th Cir.2006). Under this approach, the phrase “ ‘any felony punishable under the CSA’ is read ‘to mean any conviction punishable as a felony under the CSA.’” Rashid, 531 F.3d at 442-43. The Lopez Court did not describe its methodology as a “hypothetical federal felony approach,” and, in fact, the term “hypothetical” does not appear anywhere in the majority opinion. That is not to say that the term “hypothetical federal felony” is inapt. It simply requires additional parameters lest it grasps within its reach more than Congress intended. It does not, for example, allow an immigration court to determine that conduct for which a defendant was never charged and never convicted would have been a felony if the government had, hypothetically, prosecuted the defendant under federal law. See, e.g., Rashid, 531 F.3d at 445 (“We conclude that inclusion of the word ‘hypothetical’ in the ‘hypothetical federal felony’ approach does not provide the government with free reign to make ex-post determinations of what federal crimes an individual could hypothetically have been charged with where, as here, a prior drug-possession conviction was not at issue in the prosecution of the subsequent drug-possession offense.”); In re Carachu-ri-Rosendo, 24 I & N Dec. at 393 (noting that a pure “hypothetical approach would authorize Immigration Judges to collect a series of disjunctive facts about the respondent’s criminal history, bundle them together for the first time in removal proceedings, and then declare the resulting package to be ‘an offense’ that could have been prosecuted as a Federal felony.”)
The additional parameters needed to constrain the hypothetical federal felony come from the categorical approach which requires that, when determining which state crimes Congress intended to treat as aggravated felonies for the purposes of the INA, the court must look only to the elements of the state offense in question (and, when necessary to the charging document) to determine whether the offense corresponds to one of the crimes described as an aggravated felony under the INA. Gat-tem v. Gonzales, 412 F.3d 758, 765 (7th Cir.2005); see also Taylor v. United States, 495 U.S. 575, 602, 110 S.Ct. 2143, 109 L.Ed.2d 607 (1990) (the categorical *876approach “generally requires the trial court to look only to the fact of conviction and the statutory definition of the prior offense.”). The hypothetical federal felony and the categorical approach are not mutually exclusive. A court can, and indeed must use the categorical approach in applying the hypothetical federal felony. This is precisely the methodology the Lopez Court required when it announced that, “a state offense constitutes a felony punishable under the Controlled Substances Act only if it [that is, the state offense] proscribes conduct punishable as a felony under that federal law.” Lopez, 127 S.Ct. at 633. In other words, one looks to the description of the state offense to see whether the elements enunciated in that offense correspond to a federal felony.
The majority states that a strict categorical approach does not settle the matter in this case, but application of Lopez does. Ante at 869. This implies, however, that Lopez does not require the use of the categorical approach. In fact, Lopez demands that the categorical approach and the hypothetical federal felony be applied together. Lopez specifically instructs that, when deciding if a state offense constitutes a felony under the CSA, a tribunal must look at the conduct proscribed by the state offense. Lopez, 127 S.Ct. at 633 (emphasis added). Of course, the conduct proscribed by the state offense may not always be identical to the defendant’s conduct. There is no doubt, as the majority points out (ante at 870) that the state’s decision to classify the offense as a felony or a misdemeanor is irrelevant and the only definition that matters is the one the federal government uses to define the behavior. But this statement skirts the issue. We still need to identify which behavior we must plug into the federal classification system. Lopez tells us that it is the behavior described in the state offense.
This amalgam of the hypothetical federal felony and categorical approaches means that immigration courts may not independently assess a defendant’s conduct to determine whether such conduct would warrant a federal felony conviction, if, for example, the government had sufficient evidence to charge the defendant, if the defendant had not pled to lesser charges, if the critical evidence had not been suppressed, if a jury had found sufficient evidence of guilt, if all appeals had been unsuccessful, or if the government had opted to charge the defendant as a recidivist. Lopez constrains our hypothetical “what-ifing” to consideration of the conduct proscribed in the offense of conviction, and does not allow us to consider whether the defendant engaged in some other conduct that would have been a federal felony if a long chain of possibilities (or even one) had come to fruition. Due to prosecutorial decision making, limited resources, legal strategy, and other factors, state prosecutors often charge and convict defendants of offenses that significantly under-represent the actual conduct of the defendant. It is true that in this way, state prosecutorial decisions will affect the Department of Homeland Security’s (DHS’s) ability to remove an alien pursuant to federal immigration law. DHS, however, cannot skip the inconvenient and cumbersome hurdles imposed by criminal procedure and base decisions on convictions a state court hypothetically could have secured. When we begin to compare “an offense a defendant could have been charged with in state court with an offense the defendant could have been charged with in federal court,” we have reached “one too many levels of hypothetical application.” Pacheco-Diaz II, 513 F.3d at 781. As the Third Circuit concluded when considering the identical issue, “[o]ne cannot suffer the disabilities associated with having been convicted of an aggravated *877felony unless one has been convicted of a felony.” Steele v. Blackman, 236 F.3d 130, 136 (3d Cir.2001) (emphasis in original). Without the normal protections in place when criminal history is vetted before a court, we risk relying on constitutionally infirm convictions and elevating minor infractions into felonies in a manner unintended by Congress.
In fact, Congress recognized the inherent danger of relying on prior convictions to turn a simple misdemeanor drug offense into a recidivist felony when it drafted § 844 and § 851 of the criminal code. Under 21 U.S.C. § 851(a)(1), before the government may rely upon a prior conviction for sentencing purposes, it must file with the court, and serve on defense counsel an information revealing the previous convictions upon which it will rely. Id. The court must then give the defendant an opportunity to challenge the prior conviction and, if the defendant denies the allegations or validity of the prior conviction, hold a hearing in which the government must prove the validity or existence of the prior conviction beyond a reasonable doubt. Id. at (c)(1).1 The requirements of § 851(a) are not pro forma. If the government fails to file such notice, the court cannot use the prior conviction to enhance the penalty. United States v. LaBonte, 520 U.S. 751, 754 n. 1, 117 S.Ct. 1673, 137 L.Ed.2d 1001 (1997); United States v. Ar-reolar-Castillo, 539 F.3d 700, 703-04 (7th Cir.2008). The majority has gone to great lengths to highlight that the only thing that counts under Lopez is the federal government’s classification system (ante at 870), but it is the federal classification system that makes it clear that there can be no felony conviction under § 844(a) for a second or more drug offense unless the government gives the court and the defendant notice that it intends to use the prior convictions. 21 U.S.C. § 851.
Framed another way, the majority’s certain conclusion that the petitioners would have been subject to an increased penalty had they been charged in federal court is incorrect. The majority states:
While the state of Illinois conceivably could have enhanced the petitioners’ state sentences under the Illinois provision similar to § 844(a), that is beside the point. The question is whether the petitioners would have been subject to the increased penalty for having committed a prior drug offense had they been charged in federal court. As none of the petitioners disputes the existence of their prior convictions, the answer to that inquiry here must be “yes”; the petitioners’ most recent state possession offenses are therefore properly classified as aggravated felonies.
Ante at 871 (emphasis in original) (footnote omitted). The petitioners, however, would have been subject to the increased penalty only if they had been charged as repeat offenders under 21 U.S.C. § 851. And that is a big “if.” After all, they were not charged as repeat offenders in state court. This is the “one too many levels of hypothetical” with which we were concerned in Pacheco-Diaz. See Pacheco-Diaz II, 513 F.3d at 781.
The requirements of § 851(a) are not without good reason. As the Sixth Circuit noted, “many misdemeanor or lesser convictions are processed under questionable circumstances and may be found invalid if *878challenged.” Rashid, 531 F.3d at 447 (citing the brief amici curiae of the Criminal Defense Attorneys of Michigan and the New York State Defenders Association). The Third Circuit too commented on the danger of relying on a previous misdemeanor where its existence and constitutional integrity was never litigated as part of any criminal proceeding. Steele, 236 F.3d at 137-38. The Board of Immigration Appeals, after weighing these concerns, concluded that unless constrained by circuit law otherwise, “an alien’s State conviction for simple possession will not be considered an aggravated felony conviction on the basis of recidivism unless the alien’s status as a recidivist drug offender was either admitted by the alien or determined by a judge or jury in connection with a prosecution for that simple possession offense.” In re Carachuri-Rosendo, 24 I & N Dec. at 394. In so concluding, the Board noted that its approach differed from this Circuit’s approach in Pacheco-Diaz. Although constrained by the binding precedent of Pacheco-Diaz in this Circuit, the Board has stated that it will decline to follow the Pacheco-Diaz approach elsewhere. It is now my position that the Board and our sister courts in the First, Third, and Sixth Circuits have the better view. See, e.g., Rashid v. Mukasey, 531 F.3d 438 (6th Cir.2008); Berhe v. Gonzales, 464 F.3d 74 (1st Cir.2006); Steele v. Blackman, 236 F.3d 130 (3d Cir.2001). In short, a conviction for simple misdemeanor possession in which a court has never adjudicated or considered the fact or validity of a prior conviction should not be equated with a recidivist possession conviction under 21 U.S.C. § 844(a).
One more scenario adds weight to this conclusion. If the majority’s contrary theory is correct, then a federal defendant who has been convicted of two separate federal misdemeanor possession crimes could be deemed an aggravated felon despite the government’s failure to comply with the absolute requirements of 21 U.S.C. § 851. But we know in no uncertain terms that the government may not engage the recidivist portion of § 851 without meeting all of the requirements of that section. LaBonte, 520 U.S. at 754 n. 1, 117 S.Ct. 1673. The majority dismisses this paradox by stating that is skeptical that such a result would follow. State violations, it argues, must be compared with and then molded into the analogous federal offense of 21 U.S.C. § 844(a). Federal violations under § 844(a), the majority argues on the other hand, need not be compared to anything, and so they become recidivist crimes only if the government follows the dictates of § 851. This rationale is confusing. If the federal government deems it necessary to give a federal defendant the protections of § 851 (notice, opportunity to respond etc.) before subjecting that defendant to felony charges as a repeat offender under § 844(a), why would state recidivists— whose crimes are being analogized into the rubric of § 844(a) — not require the same protections? Surely Congress does not have more confidence in the validity of convictions from the thousands of (ofttimes minuscule, isolated, and under-resourced) state courts around the country than it has in its own federal courts. In any event, it seems clear that Congress intended for recidivists to be charged as recidivists before a court may pile on to the punishment.
This is not to say that a state recidivist law must mirror 21 U.S.C. § 851 precisely before a state recidivist can be labeled a felon pursuant to 21 U.S.C. § 844(a). One might imagine that as long as a defendant has some form of notice of and opportunity to challenge the prior conviction, then the state offense would qualify as a conviction punishable under the CSA and thus meet *879the standard declared in Lopez.2 The Sixth Circuit, in considering this question, concluded that “[pjrovided that an individual has been convicted under a state’s recidivism statute and that the elements of that offense include a prior drug-possession conviction that has become final at the time of the commission of the second offense, then that individual, under the categorical approach, has committed an aggravated felony under § 844(a).” Rashid, 531 F.3d at 448 (emphasis in original); accord In re Carachuri-Rosendo, 24 I & N Dec. at 391 (“State recidivism prosecutions must correspond to the CSA’s treatment of recidivism by providing the defendant with notice and an opportunity to be heard on whether recidivist punishment is proper.”). At this juncture we need not determine how closely the state notice and opportunities to challenge must resemble those in the federal rule. In each of the cases presented here, the petitioners were convicted of simple misdemeanors with no mention of any prior conviction. The conduct prohibited by the offenses for which they were convicted was simple possession — a crime not punishable as a felony under the CSA.
The majority hangs its hat on our recent decision in United States v. Pacheco-Diaz, 506 F.3d 545 (7th Cir.2007) (Pacheco-Diaz I), a sentencing enhancement case, wherein we concluded that the defendant’s second misdemeanor conviction for possession of marijuana would be treated as a federal felony under the recidivist provision of 21 U.S.C. § 844(a). Id. at 550. We issued the decision in Pacheco-Diaz after considering the Supreme Court’s decision in Lopez, but without the benefit of briefing on the impact of that recently released opinion, and before the Board issued its decision in Carachuri-Rosendo. Although I authored the panel decision in Pacheco-Diaz, as I noted in my dissent to the denial of rehearing, and above, I now believe that case was incorrectly decided. See Pacheco-Diaz II, 513 F.3d at 779. Our opinion in Pacheco-Diaz I looked at Pacheco-Diaz’s conduct rather than, as Lopez instructs, the conduct proscribed by the offense for which Mr. Pacheco-Diaz was convicted, and in that way did not give the categorical approach and the protective mechanisms of 21 U.S.C. § 851 their due. See Pacheco-Diaz II, 513 F.3d at 779-781 (7th Cir.2008).3
Requiring immigration courts to look at the conduct proscribed by the offense of conviction does not mean that those courts and the reviewing federal courts are beholden to the manner in which a state court *880has labeled a crime. Federal law must and does provide the classification for federal felonies. The only question is: “what is the federal law classifying?” Under a pure hypothetical federal felony approach, federal law looks at the defendant’s conduct and classifies that conduct under the federal construct regardless of the actual offense of conviction. Under the hypothetical federal felony approach modified by the categorical approach, federal law classifies the conduct for which the defendant was convicted, or, as Lopez says, the conduct proscribed by the state statute. Lopez, 127 S.Ct. at 633.
In sum, by the command of Lopez and the categorical approach to federal/state offense comparison, we are obligated to look only at the offense of conviction and the conduct described therein. True, as the majority points out, there are limited situations in which we may peek behind the face of the conviction, to the charging documents, Gattem, 412 F.3d 758, 765 (2005), but the charging documents in these cases would have been no help. In each case in this appeal the state convicted the defendant of a simple misdemeanor without mention of any previous misdemeanor convictions. The state prosecutors opted not to charge these defendants as recidivist drug crime offenders and we cannot re-write history to make it so. The offenses for which each of these petitioners were convicted do not proscribe conduct that would be a felony under the CSA. Consequently, I would hold that none of their convictions constitutes an aggravated felony under § 1101(a)(43)(B) of the INA. I respectfully dissent.
. A person may not challenge the validity of a prior conviction that is more than five years old. 21 U.S.C. § 851(e). One of the three petitioners here, Jimenez-Mateo, would have been barred from challenging the validity of his first possession offense. Presumably, however, he was still permitted to deny an allegation of the information of a prior conviction as indicated in § 851(c)(1). Furthermore, the notice requirements of 21 U.S.C. § 851(a) would still have applied.
. Illinois does have a law that provides for a sentencing enhancement for recidivist possession (720 ILCS 570/408(a)) and requires that the state give the defendant notice of the state's intention to seek the enhancement. 725 ILCS 5/111 — 3(c).
. The majority also makes much of the fact that recidivism is a penalty provision and not an element of the offense of conviction. Ante at 870 (citing Almendarez-Torres, 523 U.S. 224, 244, 118 S.Ct. 1219, 140 L.Ed.2d 350 (1998)). Although still reigning law, the viability of this notion is much in doubt. In Ap-prendi v. New Jersey, 530 U.S. 466, 520, 120 S.Ct. 2348, 147 L.Ed.2d 435, Justice Thomas, in concurrence, admitted siding with the erring position in Almendarez-Torres and con-eluded that the fact of a prior conviction is indeed an element of a recidivism statute — a position which allies him with the four dissenters in Almendarez-Torres. Id. at 520-21, 120 S.Ct. 2348 (Thomas, J., concurring). Thomas’ change of mind now means that at least five current members of the Supreme Court support the position that the fact of a prior conviction is indeed an element of a recidivism crime. In any event, this distinction does not get us around the Supreme Court’s command in Lopez that we look to the conduct proscribed in the state offense of conviction. In this case that statute described conduct — simple possession — that would not have qualified as an aggravated felony under federal law.