dissenting:
The majority concludes that the decision by the district court to proceed with 11 jurors without Curbelo’s consent is a structural error that mandates reversal without any inquiry into whether the error actually prejudiced Curbelo. Alternatively, the majority concludes that the error was not harmless because the evidence was sufficiently close that the absence of a twelfth juror may have affected the verdict. Because I disagree with both of these conclusions, I respectfully dissent.
I.
Most errors that are preserved at trial— including most constitutional errors — must be reviewed for harmlessness. See Fed. R.Crim. P. 52(a) (providing that “[a]ny error, defect, irregularity, or variance that does not affect substantial rights must be disregarded”); Neder v. United States, 527 U.S. 1, 7, 119 S.Ct. 1827, 144 L.Ed.2d 35 (1999). The Supreme Court, however, has “recognized a limited class of fundamental constitutional errors that defy analysis by harmless error standards.” Neder, 527 U.S. at 7, 119 S.Ct. 1827 (internal quotation marks omitted). “Errors of this type are so intrinsically harmful as to require automatic reversal (i.e., ‘affect substantial rights’) without regard to their effect on the outcome.” Id. Such errors include the complete deprivation of counsel, a biased trial judge, racial discrimination in the selection of a grand jury, or a defective reasonable doubt instruction. See id. at 8, 119 S.Ct. 1827 (collecting cases). These errors are always reversible because they “deprive defendants of basic protections without which a criminal trial cannot reliably serve its function as a vehicle for determination of guilt or innocence and no criminal punishment may be regarded as fundamentally fair.” Id. at 8-9, 119 S.Ct. 1827 (internal quotation marks and alteration omitted).
The majority’s determination that the error here is structural — and thus not subject to harmless error review — is incorrect for two reasons. First, this error cannot be structural because it is not of constitutional magnitude. Second, even if the er*289ror were of constitutional dimension, it would not qualify as a structural error because it did not render the trial inherently unreliable or unfair.
A.
The Supreme Court and this court have repeatedly made clear that structural errors necessarily must affect a defendant’s constitutional rights. See, e.g., Neder, 527 U.S. at 7, 119 S.Ct. 1827 (“Although [the harmless error rule] by its terms applies to all errors where a proper objection is made at trial, we have recognized a limited class of fundamental constitutional errors that defy analysis by harmless error standards.” (second emphasis added) (internal quotation marks omitted)); Rose v. Clark, 478 U.S. 570, 577, 106 S.Ct. 3101, 92 L.Ed.2d 460 (1986) (“[T]he Court in Chapman recognized that some constitutional errors require reversal without regard to the evidence in the particular case.” (emphasis added)); Arnold v. Evatt, 113 F.3d 1352, 1360 (4th Cir.1997) (“In examining the effect of constitutional errors on criminal convictions, the Supreme Court has established a distinction between structural errors, which require automatic reversal, and all other errors, which are subject to harmless-error analysis.” (emphasis added)). As other circuits have recognized, “[t]here is no separate category of structural error apart from constitutional error. The only question is whether any constitutional errors ... rise to the level of structural error.” United States v. Sanchez, 269 F.3d 1250, 1272 n. 41 (11th Cir.2001) (en banc), cert. denied, 535 U.S. 942, 122 S.Ct. 1327, 152 L.Ed.2d 234 (2002); see also Ross v. United States, 289 F.3d 677, 681 (11th Cir.2002) (per curiam) (“Structural error, to which harmless error analysis does not apply, occurs only with extreme deprivations of constitutional rights ....” (emphasis added) (internal quotation marks omitted)), cert. denied, 537 U.S. 1113, 123 S.Ct. 944, 154 L.Ed.2d 787 (2003); Bentley v. Scully, 41 F.3d 818, 823 n. 1 (2d Cir.1994) (“A ‘structural error’ requires automatic reversal and is not subject to harmless error analysis because it involves a deprivation of a [basic] constitutional protection .... ” (emphasis added)); United States v. Pavelko, 992 F.2d 32, 35 (3d Cir.1993) (“ ‘Structural defects’ deprive the criminal trial of constitutional protections ....” (emphasis added)).
Yet the error that the majority classifies as structural — the decision by the district court to proceed with 11 jurors absent Curbelo’s consent — does not implicate Curbelo’s constitutional rights. In Williams v. Florida, 399 U.S. 78, 90 S.Ct. 1893, 26 L.Ed.2d 446 (1970), the Supreme Court held that criminal defendants have no Sixth Amendment right to a 12-person jury. See Williams, 399 U.S. at 98-103, 90 S.Ct. 1893. The majority suggests that the holding of Williams may be limited to state court prosecutions and that there may be a due process right to a 12-member jury. However, in another case involving Federal Rule of Criminal Procedure 23(b), we relied on Williams in recognizing that a defendant’s “constitutional right to [a] jury trial ... does not include the right to a jury of twelve.” United States v. Fisher, 912 F.2d 728, 733 (4th Cir.1990) (citing Williams, 399 U.S. at 98-103, 90 S.Ct. 1893). And, other circuits have interpreted Williams as establishing that criminal defendants have no constitutional right to 12 jurors. See, e.g., United States v. Barone, 114 F.3d 1284, 1308 n. 21 (1st Cir.1997) (“The Supreme Court has made clear that the Constitution does not require twelve jurors for conviction. We have stated that Williams effectively answers the claim that 11 jurors are too few .... ” (citation and internal quotation marks omitted)); United States v. Smith, 789 F.2d 196, 205 (3d Cir.1986) (“It is clear *290to us that twelve jurors are not [constitutionally] required for a conviction.”); United States v. Stratton, 779 F.2d 820, 831 (2d Cir.1985) (“[T]he Supreme Court has ... made clear that the Constitution does not require twelve jurors for conviction.”).
The Supreme Court decisions cited by the majority do not support the proposition that “structural errors need not be of constitutional dimension.” Ante, at 280 n. 6. Most of those cases involve jurisdictional errors, not structural ones. See, e.g., Nguyen v. United States, — U.S. —, 123 S.Ct. 2130, 2132, 156 L.Ed.2d 64 (2003) (vacating judgments of court of appeals because panel consisting of two Article III judges and one Article IV judge did not “ha[ve] the authority to decide petitioners’ appeals”). In contrast to structural errors, which involve inherent prejudice to a particular defendant, see Neder, 527 U.S. at 7-9, 119 S.Ct. 1827, the cases cited by the majority deal with errors primarily affecting the structure and function of the judicial system. See Nguyen, 123 S.Ct. at 2137 (“[0]ur enforcement of [the designation statute’s] outer bounds is not driven so much by concern for the validity of petitioners’ convictions at trial but for the validity of the composition of the Court of Appeals.”); id. (“Even if the parties had expressly stipulated to the participation of a non-Article III judge in the consideration of their appeals ... such a stipulation would not have cured the plain defect in the composition of the panel.” (emphasis omitted)); United States v. American-Foreign S.S. Corp., 363 U.S. 685, 691, 80 S.Ct. 1336, 4 L.Ed.2d 1491 (1960) (vacating en banc court of appeals decision because retired circuit judge was “without power to participate” in that decision, and “inti-matting] no view as to the merits of the underlying litigation”).1 In each of these cases, the Supreme Court invalidated judicial proceedings involving judges who lacked the power to participate in those proceedings. These decisions are inapplicable to this case involving a violation of a procedural rule during trial by a district judge who unquestionably had jurisdiction *291to preside over the case. Indeed, I have found no decision — -and the majority has cited none — applying these holdings to trial errors involving the composition of juries.
The majority claims that the error here, like the error in Nguyen, “involves a violation of a statutory provision that ‘embodies a strong policy concerning the proper administration of judicial business’ ” and therefore should not be reviewed for harmlessness. Nguyen, 128 S.Ct. at 2137-88 (quoting Glidden Co. v. Zdanok, 370 U.S. 530, 536, 82 S.Ct. 1459, 8 L.Ed.2d 671 (1962) (plurality opinion)). But again, both Nguyen and Glidden involved jurisdictional issues concerning whether particular judges were empowered to preside over certain proceedings. Thus, it is clear that the language regarding “administration of judicial business,” as used by the Supreme Court, applies only to errors that primarily affect the court system. See American-Foreign S.S. Corp., 363 U.S. at 687, 80 S.Ct. 1336 (describing issue regarding power of retired circuit judge to participate in en banc decision as “a question of importance to the Court of Appeals in the administration of their judicial business”).
B.
Even if the error here were of constitutional magnitude, it would not amount to structural error. The Supreme Court has recognized that “most constitutional errors can be harmless.” Neder, 527 U.S. at 8, 119 S.Ct. 1827 (internal quotation marks omitted). “If the defendant had counsel and was tried by an impartial adjudicator, there is a strong presumption that any other constitutional errors that may have occurred are subject to harmless-error analysis.” Id. (internal quotation marks and alterations omitted). As explained above, the Supreme Court has “found an error to be structural, and thus subject to automatic reversal, only in a very limited class of cases,” such as those involving the complete deprivation of counsel, a biased trial judge, racial discrimination in the selection of a grand jury, or a defective reasonable doubt instruction. Id. (internal quotation marks omitted). These errors require reversal without any specific showing of prejudice to the defendant because they “necessarily render a criminal trial fundamentally unfair or an unreliable vehicle for determining guilt or innocence.” Id. at 9, 119 S.Ct. 1827.
But unlike the errors listed above— which, by their very nature, create a powerful presumption that the defendant was prejudiced — an error by a district court in proceeding with 11 jurors absent a defendant’s consent does not automatically render the trial unreliable or unfair. Rule 23(b) allows the parties to stipulate at the outset of trial that the jury will consist of fewer than 12 members. The parties may also stipulate to proceeding with fewer than 12 jurors in the event the court finds it necessary to excuse one or more jurors after trial commences. See Fed.R.Crim.P. 23(b) (amended Dec. 1, 2002). Further, the court may proceed with 11 jurors— even without the parties’ consent — if the court finds it necessary to excuse a juror after deliberations have begun. See id. Thus, Rule 23 contemplates that verdicts will sometimes be rendered, as here, by 11 rather than 12 jurors.
It is undisputed that the decision by the district court to proceed with 11 jurors violated the terms of Rule 23(b) because Curbelo declined to consent to an 11-per-son jury and deliberations had not yet begun. But the majority fails to explain how these circumstances alone make the verdict rendered by 11 jurors inherently unreliable or unfair. Indeed, the Supreme Court has specifically rejected the notion that a jury with fewer than 12 members is *292less reliable or less fair to defendants. See Williams, 399 U.S. at 100-02, 90 S.Ct. 1893.
The majority does not address the reliability and fairness concerns that the Supreme Court has made clear are at the heart of structural error analysis. Instead, my colleagues emphasize that the error here affected the entire trial and therefore its prejudicial effect cannot be quantified. But this approach overlooks the critical point that the error of proceeding with trial before 11 jurors without the defendant’s consent “does not necessarily render a criminal trial fundamentally unfair or an unreliable vehicle for determining guilt or innocence.” Neder, 527 U.S. at 9, 119 S.Ct. 1827. Indeed, under the majority’s analysis, any error that arguably had some connection to the trial as a whole — regardless of whether it affected the reliability or fairness of the trial— might be deemed structural. Cf. United States v. Lane, 474 U.S. 438, 446-49, 106 S.Ct. 725, 88 L.Ed.2d 814 (1986) (holding that misjoinder of defendants for trial, in violation of Federal Rule of Criminal Procedure 8(b), is renewable for harmlessness, and rejecting argument that such an error is per se prejudicial).
And, while the majority claims that the error here is not sufficiently quantifiable to be analyzed for harmlessness, other courts have reviewed similar errors to determine their prejudicial impact on the defendant. See United States v. Ahmad, 974 F.2d 1163, 1165-66 (9th Cir.1992) (holding that any error in conducting Rule 23(b) conference in defendant’s absence was not plain error, in part because “given the strength of the evidence against [the defendant], and the swiftness with which the jury returned its verdict, there is no reason to believe that the verdict would have been different if either [the excused juror] had been on the jury, or a different jury had heard the case”); United States v. Roby, 592 F.2d 406, 408 (8th Cir.1979) (per curiam) (holding that any violation of Rule 23(b) in failing to obtain written stipulation to use of 11-member jury was harmless because evidence against defendant was “very strong’’).2 Indeed, the Supreme Court has made clear that even the complete omission of an element of a crime from the jury charge may be reviewed for harmlessness. See Neder, 527 U.S. at 10, 119 S.Ct. 1827. In such a case, harmless error review is permitted even though the jury was never required to weigh the evidence on the omitted element and therefore no juror found all the elements necessary for conviction. See id. Here, however, 11 jurors received proper instructions on the offense elements, weighed all of the evidence, and unanimously found Curbelo guilty.
Also, the cases that the majority cites for the proposition that violations of Rule 23(b) are per se reversible error are inapplicable here. In nearly all of these cases, the district court failed to establish sufficient “just cause” for excusing a juror before proceeding with an 11-member jury, as required by Rule 23(b). The appellate decisions overturning the verdicts in these cases reflect the importance of preventing jurors — particularly those who might have “dissenting views” — from simply “opt[ing] out at will.” United States v. Essex, 734 F.2d 832, 841 (D.C.Cir.1984). *293Here, however, Curbelo does not assert that the reason articulated by the district court for excusing the juror — that she was “suffering from irritable bowel syndrome and [was] totally unable to function,” J.A. 143 — was insufficient to establish “just cause” for her excusal, or that the juror may have “opted out” because of her views on the merits of the case.3 Cf. United States v. Wilson, 894 F.2d 1245, 1250-51 (11th Cir.1990) (distinguishing Essex on the ground that district court in case at bar had established just cause for excusing juror during deliberations, and noting that “the record does not present even the slightest basis to believe that this juror was a holdout juror or that the jury had reached any sort of impasse in its deliberations”).
In sum, because the majority’s approach to structural error analysis vitiates the strong presumption in favor of harmless error review, I must dissent from the holding that the error here is structural. See Neder, 527 U.S. at 18, 119 S.Ct. 1827 (“Reversal for error, regardless of its effect on the judgment, encourages litigants to abuse the judicial process and bestirs the public to ridicule it.” (internal quotation marks omitted)); see also Sherman v. Smith, 89 F.3d 1134, 1138 (4th Cir.1996) (en banc) (emphasizing that “judges should be wary of prescribing new errors requiring automatic reversal” and that “before a court adds a new error to the list of structural errors (and thereby requires the reversal of every criminal conviction in which the error occurs), the court must be eer-tain that the error’s presence would render every such trial unfair”).
II.
Having concluded that the error by the district court in proceeding with 11 jurors was not structural, I would further hold that this error was harmless. The narcotics trafficking evidence against Curbelo was “quite simply overwhelming.” Br. of Appellee at 7. Though the majority highlights what it perceives as weaknesses in the Government’s evidence, the overall case against Curbelo on the narcotics charges was extremely strong. This evidence included a number of tape-recorded conversations among Curbelo and his associates discussing narcotics transactions; controlled purchases of narcotics from Curbelo’s place of business; testimony from several individuals describing Curbe-lo’s involvement in drug trafficking; warranted searches of Curbelo’s real property and vehicle that yielded narcotics, paraphernalia, and incriminating documents; and testimony from an ATF agent describing an interview during which Curbelo— with his attorney present — confessed in detail to drug trafficking.
In response to this compelling evidence, Curbelo “den[ied] that [he] was ever involved in drug transactions,” J.A. 403; asserted that all the Government’s witnesses were “lying,” id. at 381; and claimed that the surveillance tapes containing his voice had been “manipulated,” “edited,” and “tampered with,” id. at 408, 410. Curbelo also testified that his conversations about *294narcotics were intended to create the illusion of a “pretend simulated drug business” in order to “set a trap” for Thurnell Williams, who Curbelo believed had previously robbed his store. Id. at 394-95. However, Curbelo claimed that he was later surprised to learn that one of his main associates who was also part of these conversations was actually selling drugs to Williams. Curbelo also denied making some of the statements to the ATF agent and claimed that he had fabricated others to protect his girlfriend from prosecution.
In short, the Government presented a mountain of proof that Curbelo was guilty of narcotics trafficking. And, Curbelo’s complete denial of guilt — relying on farfetched explanations for the Government’s evidence — does not create a reasonable doubt regarding whether the twelfth juror’s absence affected the verdict. See, e.g., United States v. Blevins, 960 F.2d 1252, 1263-64 (4th Cir.1992) (holding that despite defendants’ testimony asserting their innocence, admission of improper evidence was harmless error in light of overwhelming evidence of defendants’ guilt). Also, while the record is not entirely clear, it appears that the jury reached its verdict in a matter of hours. Under these circumstances, I can say with more than “fair assurance ... that the judgment was not substantially swayed by the error” of proceeding with 11 jurors. Kotteakos v. United States, 328 U.S. 750, 765, 66 S.Ct. 1239, 90 L.Ed. 1557 (1946).4
III.
Despite the error by the district court in proceeding with 11 jurors, Curbelo received what the Constitution entitles him to: “a fair trial, not a perfect one.” Rose, 478 U.S. at 579, 106 S.Ct. 3101 (internal quotation marks omitted). “ ‘[T]he eom-monsense judgment of a group of laymen ... large enough to promote group deliberation, free from outside attempts at intimidation, and to provide a fair possibility for obtaining a representative cross-section of the community’ was interposed between [Curbelo] and his government accusers.” Fisher, 912 F.2d at 733 (quoting Williams, 399 U.S. at 100, 90 S.Ct. 1893) (first and second alterations in original). And, Cur-belo was convicted based on overwhelming evidence, with no indication that the absence of a twelfth juror had any effect on the verdict. I therefore dissent from the majority’s decision to overturn the jury’s verdict based on a nonconstitutional error that did not prejudice Curbelo. Because I believe that the other points raised by Curbelo are also meritless, I would affirm his convictions and sentences.
. One of the decisions cited by the majority includes language describing the jurisdictional error in terms of prejudice to the defendant. See Gomez v. United States, 490 U.S. 858, 876, 109 S.Ct. 2237, 104 L.Ed.2d 923 (1989) (referring to a defendant's "basic ... right to have all critical stages of a criminal trial conducted by a person with jurisdiction to preside”). But to the extent that Gomez construes a magistrate judge's involvement in jury selection in a felony trial without the defendant's consent as a structural error, that error is based on a violation of the defendant’s constitutional right to have an Article III judge preside over critical stages of trial. See Peretz v. United States, 501 U.S. 923, 929-30, 111 S.Ct. 2661, 115 L.Ed.2d 808 (1991); United States v. Amoldt, 947 F.2d 1120, 1123 (4th Cir.1991). Thus, Gomez does not support the majority's assertion that structural errors need not be constitutional in nature. And, as explained above, a defendant has no constitutional right to conviction by 12 jurors.
The majority also cites Young v. United States ex rel. Vuitton et Fils S.A., 481 U.S. 787, 107 S.Ct. 2124, 95 L.Ed.2d 740 (1987). In Young, however, only four of the nine justices concluded that the appointment of an interested private attorney to prosecute a criminal contempt action is per se reversible error because of the inherent conflict of interest. See id. at 809-14, 107 S.Ct. 2124 (Opinion of Brennan, J.). Three other justices concluded that the error should be reviewed for harmlessness. See id. at 826-27, 107 S.Ct. 2124 (Powell, J., concurring in part and dissenting in part). In any event, the error in Young— like the errors in the other cases cited by the majority, and unlike the error here — affected the proper functioning of the judicial system. Indeed, a majority of the Court in Young agreed that the exercise of the Court’s supervisory authority was appropriate because the case involved "the determination of the procedures to be employed by courts to enforce their orders, a subject that directly concerns the functioning of the Judiciary.” Id. at 809, 107 S.Ct. 2124.
. While the majority suggests that Roby dealt with a purely technical violation of Rule 23(b), the Eighth Circuit apparently assumed for purposes of decision that the lack of a written stipulation rendered invalid the defendant’s consent to proceed with 11 jurors. See Roby, 592 F.2d at 408. Nonetheless, the Eighth Circuit examined the record and determined that any such error was harmless because ”[t]he evidence ... was very strong” and "[t]here was no evidence to sustain appellant’s claim that she was being framed.” Id.
. The majority notes that "[o]ur sister circuits have also held that violations of other Federal Rules of Criminal Procedure are per se reversible.” Ante, at 285 n. 10. The Supreme Court, however, has rejected the notion that violations of the Rules of Criminal Procedure can never be reviewed for harmlessness. See Lane, 474 U.S. at 446 n. 9, 106 S.Ct. 725 ("It is difficult to see any logic in the argument that although the harmless-error rule may be applicable to constitutional violations, it should not be applied to violations of mere procedural rules.”); see also id. at 448 n. 11, 106 S.Ct. 725 (rejecting "a rule-by-rule review establishing bright-line per se rules whether to conduct harmless-error analysis” and explaining that “on its face, Rule 52(a) admits of no broad exceptions to its applicability”).
. In asserting that a 12-member jury might have reached a different verdict on the narcotics charges, the majority notes that the 11-member jury acquitted Curbelo on the charges of possessing firearms in furtherance of drug trafficking. But this argument overlooks the fact that the evidence concerning the firearms charges was different- from and much weaker than the evidence on the narcotics charges. If anything, the fact that the same 11-member jury that convicted Curbelo of all the narcotics charges also acquitted him of the firearms charges demonstrates the reliability of this jury in carefully weighing the evidence relating to each of the charges.
The majority also notes that the district court was skeptical of certain aspects of Williams’ testimony. As explained above, however, the Government presented extensive evidence against Curbelo from sources other than Williams. Thus, even independent of Williams' testimony, the Government presented a compelling case establishing Curbelo's involvement in drug trafficking.