opinion: Justice Marshall
  delivered the opinion of the Court.
  In this case, we must determine whether an alien who is prosecuted under 8 U. S. C. § 1326 for illegal entry following deportation may assert in that criminal proceeding the invalidity of the underlying deportation order.
  I-H
  Respondents, Jose Mendoza-Lopez and Angel Landeros-Quinones, were arrested at separate locations in Lincoln, Nebraska, on October 23, 1984, by agents of the Immigration and Naturalization Service. On October 30, 1984, they were transported to Denver, Colorado, where a group deportation hearing was held for respondents along with 11 other persons, all of whom were, like respondents, Mexican nationals. After the hearing, respondents were ordered deported and were bused to El Paso, Texas. They were deported from El Paso on November 1,1984. Each received, at the time of his deportation, a copy of Form 1-294, which advised, in both Spanish and English, that a return to the United States without permission following deportation would constitute a felony.
  On December 12, 1984, both respondents were once again separately arrested in Lincoln, Nebraska. They were subsequently indicted by a grand jury in the District of Nebraska on charges of violating 8 U. S. C. §1326, which provides:
  “Any alien who—
  “(1) has been arrested and deported or excluded and deported, and thereafter
  “(2) enters, attempts to enter, or is at any time found in the United States . . .
  “shall be guilty of a felony, and upon conviction thereof, be punished by imprisonment of not more than two years, or by a fine of not more than $1,000, or both.”
  Respondents moved in the District Court to dismiss their indictments, on the ground that they were denied fundamentally fair deportation hearings. They contended that the Immigration Law Judge inadequately informed them of their right to counsel at the hearing, and accepted their unknowing waivers of the right to apply for suspension of deportation.
  The District Court ruled that respondents could collaterally attack their previous deportation orders. United States v. Landeros-Quinones, CR 85-L-06 (Feb. 28, 1985). It rejected their claims that they were not adequately informed of their right to counsel. It found, however, that respondents had apparently failed to understand the Immigration Judge’s explanation of suspension of deportation. The District Court concluded that respondents had not made knowing and intelligent waivers of their rights to apply for suspension of deportation or their rights to appeal, finding it “inconceivable that they would so lightly waive their rights to appeal, and thus to the relief they now claim entitlement, [sic] if they had been fully apprised of the ramifications of such a choice.” App. to Pet. for Cert. 28a. Holding that the “failure to overcome these defendants’ lack of understanding about the proceedings, which is apparent from listening to the tape recording, totally undermined the reliability of the proceedings” and that “substantial justice was not done,” the District Court dismissed the indictments in both cases. Id., at 26a.
  The Court of Appeals for the Eighth Circuit affirmed. 781 F. 2d 111 (1985). Noting a conflict among the Circuits regarding whether a defendant prosecuted under § 1326 may collaterally attack a deportation order, the court agreed with those Courts of Appeals that had concluded that a material element of the offense prohibited by § 1326 was a “lawful” deportation. Id., at 112. It went on to state that principles of fundamental fairness required a pretrial review of the underlying deportation to examine whether the alien received due process of law. The Court of Appeals affirmed the District Court’s conclusion that there was a due process violation in this case, holding that, “[bjecause the defendants did not fully understand the proceedings, the hearing was fundamentally unfair, and the deportation order was obtained unlawfully. Thus, it cannot stand as a material element forming the basis of the charges against the defendants.” Id., at 113.
  To resolve the conflict among the Circuits, we granted certiorari. 479 U. S. 811 (1986). We affirm.
  I-H 1 — I
  In United, States v. Spector, 343 U. S. 169 (1952), we left open whether the validity of an underlying order of deportation may be challenged in a criminal prosecution in which that prior deportation is an element of the crime. Today, we squarely confront this question in the context of § 1326, which imposes a criminal penalty on any alien who has been deported and subsequently enters, attempts to enter, or is found in, the United States. The issue before us is whether a federal court must always accept as conclusive the fact of the deportation order, even if the deportation proceeding was not conducted in conformity with due process.
  The first question we must address is whether the statute itself provides for a challenge to the validity of the deportation order in a proceeding under § 1326. Some of the Courts of Appeals considering the question have held that a deportation is an element of the offense defined by § 1326 only if it is “lawful,” and that §1326 therefore permits collateral challenge to the legality of an underlying deportation order. The language of the statute, however, suggests no such limitation, stating simply that “[a]ny alien who has been arrested and deported or excluded and deported,” 8 U. S. C. § 1826 (1), will be guilty of a felony if the alien thereafter enters, attempts to enter, or is at any time found in, the United States, 8 U. S. C. § 1326(2).
  Nor does the sparse legislative history contain any evidence that Congress intended to permit challenge to the validity of the deportation in the § 1326 proceeding. Before § 1326 was enacted, three statutory sections imposed criminal penalties upon aliens who reentered the country after deportation: 8 U. S. C. § 180(a) (1946 ed.) (repealed 1952), which provided that any alien who had been “deported in pursuance of law” and subsequently entered the United States would be guilty of a felony; 8 U. S. C. § 138 (1946 ed.) (repealed 1952), which provided that an alien deported for prostitution, procuring, or similar immoral activity, and who thereafter reentered the United States, would be guilty of a misdemeanor and subject to a different penalty; and 8 U. S. C. § 137-7(b) (1946 ed., Supp. V) (repealed 1952), which stated that any alien who reentered the country after being deported for subversive activity would be guilty of a felony and subject to yet a third, more severe penalty. See H. R. Rep. No. 1365, 82d Cong., 2d Sess., 219-220 (1952).
  Congress thus had available to it in at least one of the predecessor sections — § 180(a) — express language that would have permitted collateral challenges to the validity of deportation proceedings in a criminal prosecution for reentry after deportation. It nonetheless failed to include in § 1326 the “in pursuance of law” language of § 180(a). And while there was, at the time of the enactment of § 1326, some case law suggesting that a collateral attack on a deportation proceeding might under certain circumstances be permitted, that principle was not so unequivocally established as to persuade us that Congress must have intended to incorporate that prior law into § 1326.
  The Immigration and Nationality Act does include sections that limit judicial review of deportation orders. 8 U. S. C. § 1105a provides that, outside of enumerated exceptions, the procedures prescribed by Title 28 of the United States Code for review of federal agency orders “shall be the sole and exclusive procedure for, the judicial review of all final orders of deportation.” The enumerated exceptions permit an alien to challenge a deportation order, the validity of which has not previously been judicially determined, in a criminal proceeding against the alien for violation of 8 U. S. C. §§ 1252(d) or (e), 8 U. S. C. § 1105a(a)(6), and any alien held in custody pursuant to an order of deportation may obtain judicial review of that order in a habeas corpus proceeding, 8 U. S. C. § 1105a(a)(9). These sections are not directly applicable to this case, since respondents did not ask the District Court to vacate their deportation orders and the court did not do so. It ruled only that the orders could not properly be used as the predicate for a § 1326 conviction. Yet the text of § 1105a indicates that Congress considered and addressed some of the various circumstances in which challenges to deportation orders might arise and did not mention § 1326. See also 8 U. S. C. § 1101(g) (“For the purposes of this chapter any alien ordered deported . . . who has left the United States, shall be considered to have been deported in pursuance of law . . .”); but see Mendez v. INS, 563 F. 2d 956, 959 (CA9 1977).
  The text and background of § 1326 thus indicate no congressional intent to sanction challenges to deportation orders in proceedings under § 1326.
  HH HH h-1
  That Congress did not intend the validity of the deportation order to be contestable in a § 1326 prosecution does not end our inquiry. If the statute envisions that a court may impose a criminal penalty for reentry after any deportation, regardless of how violative of the rights of the alien the deportation proceeding may have been, the statute does not comport with the constitutional requirement of due process.
  Our cases establish that where a determination made in an administrative proceeding is to play a critical role in the subsequent imposition of a criminal sanction, there must be some meaningful review of the administrative proceeding. See Estep v. United States, 327 U. S. 114, 121-122 (1946); Yakus v. United States, 321 U. S. 414, 444 (1944); cf. McKart v. United States, 395 U. S. 185, 196-197 (1969). This principle means at the very least that where the defects in an administrative proceeding foreclose judicial review of that proceeding, an alternative means of obtaining judicial review must be made available before the administrative order may be used to establish conclusively an element of a criminal offense. The result of those proceedings may subsequently be used to convert the misdemeanor of unlawful entry into the felony of unlawful entry after a deportation. Depriving an alien of the right to have the disposition in a deportation hearing reviewed in a judicial forum requires, at a minimum, that review be made available in any subsequent proceeding in which the result of the deportation proceeding is used to establish an element of a criminal offense.
  B
  Having established that a collateral challenge to the use of a deportation proceeding as an element of a criminal offense must be permitted where the deportation proceeding effectively eliminates the right of the alien to obtain judicial review, the question remains whether that occurred in this case. The United States did not seek this Court’s review of the determination of the courts below that respondents’ rights to due process were violated by the failure of the Immigration Judge to explain adequately their right to suspension of deportation or their right to appeal. Pet. for Cert. 7. The United States has asked this Court to assume that respondents’ deportation hearing was fundamentally unfair in considering whether collateral attack on the hearing may be permitted. Tr. of Oral Arg. 6-7. We consequently accept the legal conclusions of the court below that the deportation hearing violated due process. If the violation of respondents’ rights that took place in this case amounted to a complete deprivation of judicial review of the determination, that determination may not be used to enhance the penalty for an unlawful entry under § 1826. We think that it did. The Immigration Judge permitted waivers of the right to appeal that were not the result of considered judgments by respondents, and failed to advise respondents properly of their eligibility to apply for suspension of deportation. Because the waivers of their rights to appeal were not considered or intelligent, respondents were deprived of judicial review of their deportation proceeding. The Government may not, therefore, rely on those orders as reliable proof of an element of a criminal offense.
  C
  The United States asserts that our decision in Lewis v. United States, 445 U. S. 55 (1980), answered any constitutional objections to the scheme employed in §1326. In Lewis, the Court held that a state-court conviction, even though it was uncounseled and therefore obtained in violation of the Sixth and Fourteenth Amendment rights of the defendant under Gideon v. Wainwright, 372 U. S. 335 (1963), could be used as a predicate for a subsequent conviction under § 1202(a)(1) of Title VII of the Omnibus Crime Control and Safe Streets Act of 1968, as amended, 18 U. S. C. App. § 1202(a)(1), which forbade any person convicted of a felony from receiving, possessing, or transporting a firearm. We do not consider Lewis to control the issues raised by this case. The question in Lewis was whether Congress could define that “class of persons who should be disabled from dealing in or possessing firearms,” 445 U. S., at 67, by reference to prior state felony convictions, even if those convictions had resulted from procedures, such as the denial of counsel, subsequently condemned as unconstitutional. The Court there rejected Lewis’ statutory challenge, holding that Congress had manifested no intent to permit collateral attacks upon the prior state convictions in federal criminal proceedings, and further held that this use of uncounseled prior convictions did not violate the equal protection component of the Due Process Clause of the Fifth Amendment. In rejecting the notion that the statute permitted, or the Constitution required, this “new form of collateral attack” on prior convictions, the Court pointed to the availability of alternative means to secure judicial review of the conviction: “[I]t is important to note that a convicted felon may challenge the validity of a prior conviction, or otherwise remove his disability, before obtaining a firearm.” Ibid.
  It is precisely the unavailability of effective judicial review of the administrative determination at issue here that sets this case apart from Lewis. The fundamental procedural defects of the deportation hearing in this case rendered direct review of the Immigration Judge’s determination unavailable to respondents. What was assumed in Lewis, namely the opportunity to challenge the predicate conviction in a judicial forum, was precisely that which was denied to respondents here. Persons charged with crime are entitled to have the factual and legal determinations upon which convictions are based subjected to the scrutiny of an impartial judicial officer. Lewis does not reject that basic principle, and our decision today merely reaffirms it.
  Because respondents were deprived of their rights to appeal, and of any basis to appeal since the only relief for which they would have been eligible was not adequately explained to them, the deportation proceeding in which these events occurred may not be used to support a criminal conviction, and the dismissal of the indictments against them was therefore proper. The judgment of the Court of Appeals is
  Affirmed.
  Respondents have at no point raised, and we do not express any opinion regarding, the propriety of the group deportation procedure used in this ease. Compare United States v. Barraza-Leon, 575 F. 2d 218, 219-220 (CA9 1978), with United States v. Calles-Pineda, 627 F. 2d 976, 977 (CA9 1980).
  The statute excepts those aliens who have either received the express consent of the Attorney General to reapply for admission or who otherwise establish that they were not required to obtain such consent. 8 U. S. C. §§ 1326 (2)(A), (B). Respondents do not contend that either exception applies to them.
  Suspension of deportation is a discretionary remedy providing relief from deportation. The statutory section applicable to respondents makes the remedy available to a deportable alien who has been physically present in the United States for at least seven years, who was during that time a person of good moral character, and whose deportation would, in the opinion of the Attorney General, result in extreme hardship to the alien or his spouse, parent, or child, who is a United States citizen or an alien lawfully admitted to the United States for permanent residence. 8 U. S. C. § 1254(a). Suspension of deportation not only provides relief from deportation, but enables the alien to adjust his status to that of an alien lawfully admitted for permanent residence. Ibid.
  The District Court found that the Immigration Judge did not answer a question from one of the respondents regarding application for suspension of deportation; that the Immigration Judge addressed the wrong respondent while discussing eligibility for the remedy; that the Immigration Judge did not make clear how much time he would allow respondents to apply for suspension; and that Landeros-Quinones asked a question which demonstrated that he did not understand the concept of suspension of deportation, but that the Immigration Judge failed to explain further. The District Court contrasted this cursory and confusing treatment of the issue of suspension of deportation with the extensive inquiry that took place when two of the other aliens sought voluntary departure in lieu of deportation, one of whom was ultimately granted voluntary departure. App. to Pet. for Cert. 20a-22a.
  One judge dissented on the ground that a challenge to the propriety of a previous deportation order may never be asserted in a criminal proceeding under § 1326. 781 F. 2d, at 113-114.
  Compare, e. g., United States v. Nicholas-Armenta, 763 F. 2d 1089, 1090 (CA9 1985), and United States v. Bowles, 331 F. 2d 742, 749-750 (CA3 1964) (collateral attack on legality of deportation permitted in § 1326 proceeding), with United States v. Petrella, 707 F. 2d 64, 66 (CA2), cert. denied, 464 U. S. 921 (1983), United States v. Gonzalez-Parra, 438 F. 2d 694, 697 (CA5), cert. denied, 402 U. S. 1010 (1971), and Arriaga-Ramirez v. United States, 325 F. 2d 857, 859 (CA10 1963) (collateral attacks barred in prosecutions under § 1326); see also United States v. Rosal-Aguilar, 652 F. 2d 721, 723 (CA7 1981) (trial de novo on the factual basis of the underlying deportation is not a constitutional prerequisite to conviction under § 1326, but “the Government must prove the underlying deportation to have been based on a valid legal predicate and obtained according to law”); Petrella v. United States, 464 U. S. 921, 922 (1983) (White, J., dissenting from denial of certiorari) (internal quotation omitted).
  In Spector, an alien against whom an order of deportation was outstanding was prosecuted for failure to make timely application for documents necessary to his departure. He challenged the statute on vagueness grounds and prevailed in the District Court. The case was appealed directly to this Court, which ruled that the statute was not void for vagueness. 343 U. S., at 171-172. The Court noted the argument that the statute was unconstitutional because it afforded no opportunity for the court trying the criminal charge to pass on the validity of the order of deportation, but declined to address the issue because it “was neither raised by the appellee nor briefed nor argued here.” Id., at 172. “It will be time to consider whether the validity of the order of deportation may be tried in the criminal trial. . . when and if the appellee seeks to have it tried. That question is not foreclosed by this opinion. We reserve decision on it.” Id., at 172-173.
  Justice Jackson, with whom Justice Frankfurter joined, dissented on the ground that the statute at issue impermissibly allowed the use of an administrative determination as conclusive evidence of a fact in a criminal prosecution. “Having thus dispensed with important constitutional safeguards in obtaining an administrative adjudication that the alien is guilty of conduct making him deportable on the ground it is only a civil proceeding, the Government seeks to turn around and use the result as a conclusive determination of that fact in a criminal proceeding. We think it cannot make that use of such an order.” Id., at 179.
  Congress resolved the potential problem in Spector when, in 1961, it enacted 8 U. S. C. § 1105a(a)(6), which provides explicitly that, if the validity of a deportation order has not been judicially determined, it may be challenged in a criminal proceeding against the alien under 8 U. S. C. § 1252(e) for willfully failing or refusing to make timely application in good faith for travel or other documents necessary to his departure. Section 1105a does not explicitly address the availability of collateral attack under § 1326.
  In its petition for certiorari, the United States did not seek review of the Court of Appeals’ holding that the deportation proceeding in this case was fundamentally unfair and that the deportation order was therefore unlawful. Pet. for Cert. 7.
  See, e. g., United States v. Gasca-Kraft, 522 F. 2d 149, 152 (CA9 1975) (“A material element of the offense defined by 8 U. S. C. § 1326 is a lawful deportation”); United States v. Bowles, supra, at 749 (“When Congress made use of the word ‘deported’ in the statute, it meant ‘deported according to law’ ”). The Court of Appeals for the Eighth Circuit, in deciding this case, noted that other courts had permitted collateral attack on the ground that “a material element of the offense prohibited by 8 U. S. C. § 1326 is a ‘lawful’ deportation” and stated that it “agree[d] with this rationale.” 781 F. 2d, at 112. The court does not appear to have relied entirely on the statute in ruling that the propriety of the deportation could be reviewed in the § 1326 proceeding, since it then continued: “Allowing a pretrial review of the underlying deportation to examine whether due process was provided insures fundamental fairness to the rights of the criminal defendant. Accordingly, we conclude that defendants in section 1326 prosecutions may collaterally attack their previous deportation orders on the ground that they were not accorded due process at the deportation hearing.” Id., at 112-113.
  Section 180(a) provided for punishment by imprisonment of not more than two years or a fine of not more than $1,000, or both; § 138 provided solely for imprisonment for up to two years; § 137-7(b) provided for imprisonment for up to five years. The purpose of § 1326 was to impose the same penalty on any person who returned to the United States without permission after deportation, regardless of the basis of the original deportation. See S. Rep. No. 1515, 81st Cong., 2d Sess., 655, 656 (1950).
  That Congress had before it the text of all three sections was clear— their text was in all pertinent respects reproduced as “existing law” in the House Report on the statute that included § 1326. H. R. Rep. No. 1365, 82d Cong., 2d Sess., 219-220 (1952).
  See, e. g., United States ex rel. Beck v. Neelly, 202 F. 2d 221, 222, 224 (CA7) (declining to decide whether deported alien may challenge prior deportation in habeas corpus proceeding), cert. denied, 345 U. S. 997 (1953); United States ex rel. Steffner v. Carmichael, 183 F. 2d 19, 20 (CA5) (collateral attack on deportation proceeding in later deportation proceeding impermissible unless there was “gross miscarriage of justice” in the former proceeding; prior order here was valid), cert. denied, 340 U. S. 829 (1950); Daskaloff v. Zurbrick, 103 F. 2d 579, 580-581 (CA6 1939) (alien deported as a prostitute who reentered country and was detained on warrant of deportation under 8 U. S. C. § 155 (1946 ed.) (repealed 1952) could not collaterally attack validity of earlier deportation through habeas corpus).
  Contrary to Justice Scalia’s suggestion, post, at 849, our opinion today does not reject the holding in Mendez, as to which we express no view. '
  The Government stated at oral argument that it was the position of the United States that there were “absolutely no due process limitations to the enforcement of Section 1326.” Tr. of Oral Arg. 10.
  Even with this safeguard, the use of the result of an administrative proceeding to establish an element of a criminal offense is troubling. See United States v. Spector, 343 U. S. 169, 179 (1952) (Jackson, J., dissenting). While the Court has permitted criminal conviction for violation of an administrative regulation where the validity of the regulation could not be challenged in the criminal proceeding, Yakus v. United States, 321 U. S. 414 (1944), the decision in that case was motivated by the exigencies of wartime, dealt with the propriety of regulations rather than the legitimacy of an adjudicative procedure, and, most significantly, turned on the fact that adequate judicial review of the validity of the regulation was available in another forum. Under different circumstances, the propriety of using an administrative ruling in such a way remains open to question. We do not reach this issue here, however, holding that, at a minimum, the result of an administrative proceeding may not be used as a conclusive element of a criminal offense where the judicial review that legitimated such a practice in the first instance has effectively been denied.
  A number of commentators have expressed the notion that, where the deportation proceeding violated fundamental fairness, its validity may be challenged in a criminal proceeding under § 1326. See, e. g., Comment, Collateral Attacks on Deportation Orders in Prosecutions for Illegal Reentry, 48 U. Chi. L. Rev. 83, 90-91, 102-103 (1981) (where alien was denied fundamental fairness at the deportation hearing, collateral attacks in § 1326 proceedings would be proper); Note, Collaterally Attacking Deportation Orders in Criminal Prosecutions for Illegal Reentry Under Section 276 of the Immigration and Nationality Act of 1952, 56 Notre Dame Law. 677, 686-688 (1981) (fundamental fairness requires some form of collateral review of civil deportation proceedings which have criminal consequences).
  We decline at this stage to enumerate which procedural errors are so fundamental that they may functionally deprive the alien of judicial review, requiring that the result of the hearing in which they took place not be used to support a criminal conviction. We have previously recognized, however, in the context of criminal proceedings, that “some errors necessarily render a trial fundamentally unfair,” Rose v. Clark, 478 U. S. 570, 577 (1986) (use of coerced confession, adjudication by a biased judge); see also Rose v. Lundy, 455 U. S. 509, 543-544 (1982) (Stevens, J., dissenting) (mob violence, knowing use of perjured testimony). While the procedures required in an administrative proceeding are less stringent than those demanded in a criminal trial, analogous abuses could operate, under some circumstances, to deny effective judicial review of administrative determinations.
  We note parenthetically that permitting collateral challenge to the validity of deportation orders in proceedings under § 1326 does not create an opportunity for aliens to delay deportation, since the collateral challenge we recognize today is available only in criminal proceedings instituted after reentry.
  Cf. Burgett v. Texas, 389 U. S. 109, 115 (1967); see also Baldasar v. Illinois, 446 U. S. 222, 226-227 (1980) (MARSHALL, J., concurring) (court may not constitutionally use prior uncounseled misdemeanor conviction collaterally to enhance a subsequent misdemeanor to a felony with an increased term of imprisonment); United States v. Tucker, 404 U. S. 443 (1972) (court may not consider constitutionally invalid prior convictions in imposing sentence on unrelated offense); see also 8 U. S. C. § 1325, which provides that an unlawful entry into the United States constitutes a misdemeanor. Section 1326 serves to enhance the penalty for unlawful entry, imposing a steeper punishment on individuals who violate § 1325 and who have previously been deported.