Justice O'CONNOR, with whom Justice Stevens, Justice Souter, and Justice Breyer join, dissenting.
José Ernesto Medellín offered proof to the Court of Appeals that reasonable jurists would find debatable or wrong the District Courts disposition of his claim that Texas violated his rights under the Vienna Convention on Consular Relations and that he is thereby entitled to review and reconsideration of his conviction and sentence. Three specific issues deserve further consideration: (1) whether the International Court of Justices judgment in Medellíns favor, Case Concerning Avena and Other Mexican Nationals (Mex. v. U. S.), 2004 I. C. J. No. 128 (Judgment of Mar. 31), is binding on American courts; (2) whether Article 36(1)(b) of the Convention creates a judicially enforceable individual right; and (3) whether Article 36(2) of the Convention sometimes requires state procedural default rules to be set aside so that the treaty can be given full effect. Accordingly, I would vacate the denial of a certificate of appealability and remand for resolution of these issues.
The Court dismisses the writ (and terminates federal proceedings) on the basis of speculation: Medellín might obtain relief in new state court proceedingsbecause of the Presidents recent memorandum about whose constitutionality the Court remains rightfully agnostic, or he might be unable to secure ultimate relief in federal courtbecause of questions about whose resolution the Court is likewise, rightfully, undecided. These tentative predictions are not, in my view, reason enough to avoid questions that are as compelling now as they were when we granted a writ of certiorari, and that remain properly before this Court. It seems to me unsound to avoid questions of national importance when they are bound to recur. I respectfully dissent.
I
Article 36 of the Vienna Convention on Consular Relations guarantees open channels of communication between detained foreign nationals and their consulates in signatory countries:
[I]f he so requests, the competent authorities of the receiving State shall, without delay, inform the consular post of the sending State if, within its consular district, a national of that State is arrested or committed to prison or to custody pending trial or is detained in any other manner. Any communication addressed to the consular post by the person arrested, in prison, custody or detention shall also be forwarded by the said authorities without delay. The said authorities shall inform the person concerned without delay of his rights under this sub-paragraph. Vienna Convention on Consular Relations, Art. 36(1)(b), Apr. 24, 1963, [1970] 21 U. S. T. 77, 101, T. I. A. S. No. 6820.
Presently 167 nations are party to the Vienna Convention, including our immediate neighbors to the north and south. Multilateral Treaties Deposited with the Secretary-General United Nations, N. Y., http://untreaty.un.org (all Internet materials as visited May 19, 2005, and available in Clerk of Courts case file).
In this country, the individual States (often confessed) noncompliance with the treaty has been a vexing problem. See, e.g., United States v . Emuegbunam, 268 F. 3d 377, 391 (CA6 2001) (discussing cases about Vienna Convention violations). It has three times been the subject of proceedings in the International Court of Justice (ICJ). See Case Concerning Vienna Convention on Consular Relations (Para. v. U. S.), 1998 I. C. J. 426 (Order of Nov. 10); LaGrand Case (F. R. G. v. U. S.), 2001 I. C. J. 466 (Judgment of June 27); Avena, supra. The problem may have considerable ramifications, because foreign nationals are regularly subject to state criminal justice systems. For example, in 2003, over 56,000 noncitizens were held in state prisons. Noncitizens accounted for over 10% of the prison populations in California, New York, and Arizona. U. S. Dept. of Justice, Bureau of Justice Statistics Bull. p. 5 (rev. July 14, 2004), Prison and Jail Inmates at Midyear 2003, http://www.ojp.usdoj.gov/ bjs/pub/pdf/pjim03.pdf.
Noncompliance with our treaty obligations is especially worrisome in capital cases. As of February 2005, 119 noncitizens from 31 nations were on state death row. Foreign Nationals and the Death Penalty in the United States, Reported Foreign Nationals Under Sentence of Death in the U. S., http://www.deathpenaltyinfo.org/ article.php?did=198&scid;=31. In Avena, the ICJ determined that the United States had breached its obligation to inform 51 Mexican nationals, all sentenced to death in this country, of their right to consular notification. Medellín is just one of them. 2004 I. C. J. No. 128, ¶106. His case thus presents, and the Court in turn avoids, questions that will inevitably recur.
José Ernesto Medellín told the officers who arrested him in Texas that he was born in Laredo, Mexico. App. JA 15. He also told the Harris County Pretrial Services that he is not an American citizen. App. to Pet. for Cert. 165a. Nonetheless, Medellín was arrested, detained, tried, convicted, and sentenced to death without ever being informed that he could contact the Mexican consul. Mexican consular authorities only became aware of Medellíns predicament some six weeks after his conviction was affirmed, when he wrote them a letter from Texas death row. Since coming into contact with his consul, Medellín has maintained that Texas authorities violated his rights under the Convention and has sought (among other relief) an evidentiary hearing to determine whether he was prejudiced by the violation.
First, Medellín filed a state application for a writ of habeas corpus. The Texas trial court denied relief, reasoning in relevant part:
13.Based on the applicants lack of objection at trial to the alleged failure to inform him of his rights under the Vienna Convention, the applicant is procedurally barred from presenting his habeas claim that the alleged violation of the Vienna Convention violated his constitutional rights. Hodge v. State, 631 S. W. 2d 754, 757 (Tex. Crim. App. 1982); Williams v. State, 549 S. W. 2d 183, 187 (Tex. Crim. App. 1977).
…..
15.In the alternative, the applicant, as a private individual, lacks standing to enforce the provisions of the Vienna Convention. Hinojosa v. State, No. 72,932 (Tex. Crim. App. Oct. 27, 1999) (holding that treaties operate as contracts among nations; thus, offended nation, not individual, must seek redress for violation of sovereign interests). Id., at 55a56a.
The Texas Court of Criminal Appeals affirmed.
Medellín next petitioned for habeas relief in the United States District Court for the Southern District of Texas. While that petition was pending, the ICJ announced its interpretation of Article 36 in a case that Germany had brought against the United States after Arizona failed to advise two German capital defendants about consular notification. LaGrand, supra. Consistent with Medellíns own arguments about the Conventions meaning, the ICJ decided in LaGrand that the treaty confers individual rights and requires that state procedural default rules sometimes give way when foreign national defendants raise Vienna Convention claims. See id., at 490491, 497498. Medellín argued to the District Court that the ICJs interpretation of Article 36 was definitive, persuasive, and should control the resolution of his claim. Rejecting these and other arguments, the District Court denied relief.
Medellín then sought to obtain a certificate of appealability (COA) from the United States Court of Appeals for the Fifth Circuit. See 28 U. S. C. §2253(c). A COA may issue only if the applicant has demonstrated that reasonable jurists could debate whether (or, for that matter, agree that) the petition should have been resolved in a different manner [in the district court] or that the issues presented were adequate to deserve encouragement to proceed further. Slack v. McDaniel, 529 U. S. 473, 484 (2000) (quoting Barefoot v. Estelle, 463 U. S. 880, 893, n. 4 (1983)).
Meanwhile, Mexico had initiated proceedings in the ICJ against the United States on grounds that 54 Mexican capital defendants, including Medellín, had been denied their Vienna Convention rights. See Avena, supra. The ICJs decision in Avena issued while Medellíns application for a COA was pending. Repeating the construction it had given to Article 36 in LaGrand, the ICJ decided that Medellín and 50 others were entitled to review and reconsideration of their convictions and sentences because the United States, through various individual States, had violated their Vienna Convention rights. Avena, supra, ¶153. The Court of Appeals noted the ICJs pronouncements in LaGrand and Avena, and nonetheless concluded that Medellíns treaty claim lacked the requisite merit for a COA.
We granted certiorari on two questions. First, does Avena have preclusive effect in our courts? Second, if our courts are not bound to apply Avena as a rule of decision, must they give the ICJs decision effect for sake of uniform treaty interpretation or comity? These questions refer to substantial, debatable issues in Medellíns Vienna Convention claim. I would therefore vacate the denial of a COA and remand for further proceedings.
II
A
At every step, the federal courts must evaluate Medellíns Vienna Convention claim through the framework of the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA), which controls the process by which a state prisoner may obtain federal habeas relief. And wherever the Convention, which has been in continuous force since 1969, conflicts with this subsequently enacted statute, the statute must govern. Reid v. Covert, 354 U. S. 1, 18 (1957) (plurality opinion); see also Whitney v. Robertson, 124 U. S. 190, 194 (1888).
At the outset, Texas and the United States argue that AEDPAs §2253(c) precludes ruling for Medellín no matter how meritorious his Vienna Convention claim may be. According to §2253(c)(2), a COA may issue only if the applicant has made a substantial showing of the denial of a constitutional right. Texas maintains that prisoners may only appeal district courts adverse decisions involving constitutional rightsthat Congress did not use the word constitutional in the statute as shorthand for all of the federal claims traditionally heard in habeas. But see 1 R. Hertz & J. Liebman, Federal Habeas Corpus Practice and Procedure 448449 (4th ed. 2001). See also Slack, supra, at 483 (noting Congress substitution of constitutional for federal in the standard for obtaining a certificate of probable causethe COAs predecessorwithout saying if the change is meaningful).
Texas concedes that it raised this objection for the first time in its merits brief to this Court. Tr. of Oral Arg. 29. Normally this Court will not decide a question raised at this stage. See Taylor v. Freeland & Kronz, 503 U. S. 638, 645646 (1992). But Texas contends that this is a nonwaivable jurisdictional objection. So we must start with the question of whether it actually is an objection that cannot be waived. It is true that the COA is jurisdictional in the sense that it is a gateway device. Miller-El v. Cockrell, 537 U. S. 322, 337 (2003). By obliging applicants to make a threshold showing before their cases are aired out on appeal, the COA serves an important screening function and conserves the resources of appellate courts. To that end, the existence of a COA is jurisdictional insofar as a prisoner cannot appeal in habeas without one. See id., at 335336. Accordingly, a federal court must verify that that a COA has issued before hearing the merits of a habeas appeal.
It does not follow, however, that courts must raise and decide predicate arguments about the validity of a COA independently, without prompting from the parties, even when ordinary waiver rules would apply, as they must with true jurisdictional arguments. If that were so, an appellate court, presiding over an appeal after the district court had issued a COA, would always be required to check that a substantial showing had been made and a cognizable right assertedeven in the absence of controversy between the parties. We have never imposed such a rule, and it would undermine the efficiency of the COA process. Cf. Young v. United States, 124 F. 3d 794, 799 (CA7 1997). Predicate considerations for a COAwhether a substantial showing has been made or a constitutional right assertedare not the sorts of considerations that remain open for review throughout the entire case. Compare Peguero v. United States, 526 U. S. 23 (1999) (considering whether a violation of Federal Rule of Criminal Procedure 32(a)(2) provided a basis for collateral relief), with Brief for United States in Peguero v. United States, O. T. 1998, No. 979217, p. 6, n. 5 (arguing that §2253(c) deprived the Court of jurisdiction because a constitutional right was not at stake). Thus, because Texas did not argue below that a treaty-based claim cannot support an application for a COA, it cannot raise the argument now.
Texas also adverts to another AEDPA provision, 28 U. S. C. §2254(d), which it says is fatal to Medellíns treaty claim. The statute provides that a writ of habeas corpus shall not issue on behalf of a person in state custody with respect to any claim adjudicated on the merits in State court proceedings unless the adjudication of the claim(1) resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States. Whether Medellíns claim clears these hurdles is an appropriate consideration for an appellate court contemplating whether to grant a COA, and for this Court reviewing the denial of a COA. See Miller-El, 537 U. S., at 349350 (Scalia, J., concurring) (A circuit justice or judge must deny a COA if all reasonable jurists would conclude that a substantive provision of the federal habeas statute bars relief); see also id., at 336.
The Texas courts disposition of Medellíns Vienna Convention claim is not entitled to deference under §2254(d), and thus should not constrain a final decision in federal court about whether he deserves habeas relief. The Texas court gave two reasons for dismissing the claim. First, it applied its procedural default rule to Medellíns assertion of right under the Vienna Convention. See supra, at 4. In so doing, it did not adjudicate the merits of the relevant federal questionwhether, under Article 36(2), the treaty overrides state procedural default rules. Second, the Texas court appears to have reasoned that private individuals (as opposed to offended nations) can never enforce any treaty in court. See supra, at 4. This reasoning is contrary to our precedents and, therefore, is not entitled to deference in subsequent federal proceedings. A state-court decision will certainly be contrary to our clearly established precedent if the state court applies a rule that contradicts the governing law set forth in our cases. Williams v. Taylor, 529 U. S. 362, 405 (2000); see also Brown v. Payton, ante, at 7. The Texas courts blanket rule plainly contradicts our governing law, for it is axiomatic that, while treaties are compacts between nations, a treaty may also contain provisions which confer certain rights upon the citizens or subjects of one of the nations residing in the territorial limits of the other, which partake of the nature of municipal law, and which are capable of enforcement as between private parties in the courts of the country. Head Money Cases, 112 U. S. 580, 598 (1884). The Texas court neither asked nor answered the right question: whether an individual can bring a claim under this particular treaty. Accordingly, any consideration of Medellíns Vienna Convention claim for habeas relief in federal courtincluding his assertion that Avena provides a binding rule of decisionmust proceed de novo. See Williams, supra, at 406.
B
The Court catalogs a number of other, nonjurisdictional questions that, in its view, justify dismissing the case because they could preclude ultimate habeas relief for Medellín. Ante, at 45. Apparently the Court agrees that it would be impossible or imprudent to decide these questions today. It seems odd to me to leave them undecided and yet to rely on them as reason to avoid the weighty questions that are undeniably properly before us. Given the posture of this case, our modest task is to decide only whether Medellín has presented claims worthy of a COA, and the majority points to issues outside the scope of that inquiry. Anyway, it is not our practice generally, when remanding a case to the lower courts after resolving discrete questions, to canvass all of the possible permutations of what could happen before a final resolution. Thus, while the Court points to questions that are, of course, important, none ought to detain us here.
First, Texas and the United States have made no mention of Reed v. Farley, 512 U. S. 339 (1994), and Hill v. United States, 368 U. S. 424 (1962), depriving Medellín of an opportunity to discuss their applicability to his casea complicated question. Second, while Texas did argue in its certiorari papers that Medellín had already received a prejudice analysis in state habeas, see Brief in Opposition 1416, it abandoned this argument in its brief on the merits. See United States v. International Business Machines Corp., 517 U. S. 843, 855, n. 3 (1996) (the Court does not address abandoned arguments). Here, Texas argues that Medellín cannot show prejudice in a future proceeding, not that he has already failed to show prejudice or that the state court thought (not unreasonably) that the Vienna Convention had been satisfied by its prejudice analysis. See Brief for Respondent 1617. Moreover, Medellín has maintained an unfulfilled request for an evidentiary hearing about prejudice. The ICJ, for its part, appears to believe that Medellín has yet to receive the prejudice analysis that the Vienna Convention requires; otherwise, it would not have ruledafter the state habeas proceedings had concludedthat the United States must still provide review and reconsideration of his sentence to determine if he suffered actual prejudice. Avena, 2004 I. C. J. No. 128, ¶¶121122, 153. Third, the Court is correct to observe that, before obtaining relief, Medellín would have to contend with Teague v. Lane, 489 U. S. 288 (1989). The Court of Appeals never discussed Teague s applicability to Medellíns case. Whether Teague bars relief for Medellín is itself a highly debatable question that should be part of a proper COA analysis upon remand.
III
While a COA ruling is not the occasion for a ruling on the merit of petitioners claim, Miller-El, 537 U. S., at 331, some assessment of Medellíns arguments is necessary to explain why the COAs denial should be vacated.
A
The Optional Protocol to the Vienna Convention provides that [d]isputes arising out of the interpretation or application of the Convention shall lie within the compulsory jurisdiction of the International Court of Justice. Optional Protocol Concerning the Compulsory Settlement of Disputes, Apr. 18, 1961, Art. I [1970] 21 U. S. T. 326, T. I. A. S. No. 6820 (hereinafter Optional Protocol). The United States was party to the Optional Protocol until recently. See Letter from Condoleezza Rice, Secretary of State, to Kofi A. Annan, Secretary-General of the United Nations (Mar. 7, 2005) (notifying the Secretary-General that the United States hereby withdraws from the Optional Protocol). And the ICJ decided LaGrand and Avena pursuant to the Optional Protocols grant of authority. The first question on which we granted certiorari asks whether American courts are now bound to follow the ICJs decision in Avena when deciding Vienna Convention claims.[ Footnote 1 ]
If Medellín is right to say that they must, then the District Courts resolution of his Vienna Convention claim is not merely debatable, but wrong in result and in reasoning. In terms of result, the ICJ made clear that it would be improper to dismiss Medellíns claim, for once the United States had committed internationally wrongful acts, the necessary remedy to make good these violations should consist in an obligation on the United States to permit review and reconsideration of [the 51 Mexican] nationals cases by the United States courts. Avena, 2004 I. C. J. No. 128, ¶121. The ICJs reasoning is also irreconcilable with the District Courts. The ICJ specified that the Convention confers rights on individual defendants, and that applying state procedural default rules to prevent them from vindicating their rights violates the treaty, for the treaty requires that its purposes be given full effect. Id., ¶¶106, 113.
Medellín argues that once the United States undertakes a substantive obligation (as it did in the Vienna Convention), and at the same time undertakes to abide by the result of a specified dispute resolution process (as it did by submitting to the ICJs jurisdiction through the Optional Protocol), it is bound by the rules generated by that process no less than it is by the treaty that is the source of the substantive obligation. In other words, because Avena was decided on the back of a self-executing treaty, see infra, at 15, it must be given effect in our domestic legal system just as the treaty itself must be. Medellín asserts, at bottom, that Avena, like a treaty, has the status of supreme law of the land.
On the other hand, Texas and the United States argue that the issue turns in large part on how to interpret Article 94(1) of the United Nations Charter, which provides that [e]ach Member of the United Nations undertakes to comply with the decision of the International Court of Justice in any case to which it is a party. 59 Stat. 1051. They maintain that the charter imposes an international duty only on our political branches. A contrary result could deprive the Executive of necessary discretion in foreign relations, and may improperly displace this Courts responsibilities to an international body. For his part, Medellín says that Article 94(1) cannot answer the question of whether, under domestic law and the Supremacy Clause, our courts are bound to comply with the international obligation reflected in Avena.
The Court of Appeals passed on whether it was bound by Avena, and decided that the issue was not worthy of a COA. In so doing, it noted some conflict between Avena and our decision in Breard v. Greene, 523 U. S. 371, 376 (1998) (per curiam). How to resolve that conflict is a difficult question. Reasonable jurists can vigorously disagree about whether and what legal effect ICJ decisions have in our domestic courts, and about whether Medellín can benefit from such effect in this posture. The Court of Appeals should have granted a COA and given the issue further consideration.
B
We also granted certiorari on a second, alternative question that asks whether and what weight American courts should give to Avena, perhaps for sake of uniform treaty interpretation, even if they are not bound to follow the ICJs decision. That question can only be answered by holding up the Avena interpretation of the treaty against the domestic courts own conclusions, and then deciding how and to what extent the two should be reconciled. See Olympic Airways v. Husain, 540 U. S. 644, 660661 (2004) (Scalia, J., dissenting); Air France v. Saks, 470 U. S. 392, 404 (1985). Accordingly, the second question presented encompassed two other issues, both pressed and passed upon below, that are themselves debatable and thus grounds for a COA: whether the Vienna Convention creates judicially enforceable rights and whether it sometimes trumps state procedural default rules.[ Footnote 2 ]
This Court has remarked that Article 36 of the Vienna Convention arguably confers on an individual the right to consular assistance following arrest. Breard, supra, at 376. The United States maintains, on the contrary, that Article 36 does not give foreign nationals a judicially enforceable right to consular access. On that theory, a detained foreign national may never complain in courteven in the course of a trial or on direct reviewabout a states failure to inform the person concerned without delay of his rights under Article 36. 21 U. S. T., at 101. The complainant must be the sending state, and any remedy is political, diplomatic, or between the states in international law.
When called upon to interpret a treaty in a given case or controversy, we give considerable weight to the Executive Branchs understanding of our treaty obligations. See Kolovrat v. Oregon, 366 U. S. 187, 194 (1961); Charlton v. Kelly, 229 U. S. 447, 468 (1913). But a treatys meaning is not beyond debate once the Executive has interpreted it. Cf., e.g., Chan v. Korean Air Lines, Ltd., 490 U. S. 122, 136 (1989) (Brennan, J., concurring in judgment) (observing that the Court was rejecting a view of the Warsaw Convention that had consistently been adopted by the Executive Branch and had been pressed by the United States in that case); Perkins v. Elg, 307 U. S. 325, 328, 337342 (1939) (declining to adopt Executives treaty interpretation); Johnson v. Browne, 205 U. S. 309, 319321 (1907) (same); De Lima v. Bidwell, 182 U. S. 1, 181, 194199 (1901) (same).
Article 36 of the Vienna Convention on Consular Relations is, as the United States recognizes, a self-executing treaty. Brief for United States as Amicus Curiae 26. Chief Justice Marshall explained that a self-executing treaty is domestic law. It operates of itself, as a rule for the Court, equivalent to an act of the legislature. Foster v. Neilson, 2 Pet. 253, 314 (1829). Because the Convention is self-executing, then, its guarantees are susceptible to judicial enforcement just as the provisions of a statute would be. See Head Money Cases, 112 U. S., at 598599 (A treaty, then, is a law of the land as an act of Congress is, whenever its provisions prescribe a rule by which the rights of the private citizen or subject may be determined. And when such rights are of a nature to be enforced in a court of justice, that court resorts to the treaty for a rule of decision for the case before it as it would to a statute); see generally L. Henkin, Foreign Affairs and the United States Constitution 206209 (2d ed. 1996).
To ascertain whether Article 36 confers a right on individuals, we first look to the treatys text as we would with a statutes. United States v. Alvarez-Machain, 504 U. S. 655, 663 (1992); Air France v. Saks, 470 U. S., at 397. Article 36(1)(b) entails three different obligations for signatory host countries. Their competent authorities shall (1) inform the consul of its nationals detentions, (2) forward communication from a detained national to his consulate, and (3) inform the person concerned without delay of his rights under this sub-paragraph. 21 U. S. T., at 101 (emphasis added). Of these, the third exclusively concerns the detained individual, and it is the only obligation expressed in the language of rights. If Article 36(1) conferred no rights on the detained individual, its command to inform the detainee of his rights might be meaningless. Other provisions in the treaty appear to refer back to individual rights. See Art. 36(1)(a), ibid.; Art. 36(2), ibid.
To be sure, the questions of whether a treaty is self-executing and whether it creates private rights and remedies are analytically distinct. If Article 36(1)(b) imposed only two obligations on signatory countriesto notify the consul and forward correspondencethen Medellín could not invoke the treaty as a source of personal rights by virtue of its self-executing character. But the treaty goes furtherimposing an obligation to inform the individual of his rights in the treaty. And if a statute were to provide, for example, that arresting authorities shall inform a detained person without delay of his right to counsel, I question whether more would be required before a defendant could invoke that statute to complain in court if he had not been so informed.
This Court has repeatedly enforced treaty-based rights of individual foreigners, allowing them to assert claims arising from various treaties. These treaties, often regarding reciprocity in commerce and navigation, do not share any special magic words. Their rights-conferring language is arguably no clearer than the Vienna Conventions is, and they do not specify judicial enforcement. See, e.g., Asakura v. Seattle, 265 U. S. 332, 340 (1924) (allowing Japanese national to bring a claim under a United States-Japan treaty requiring that citizens or subjects of each of the [two countries] shall have liberty to carry on trade in the others territory, and holding that a local licensing ordinance for pawnbrokers could not be applied to the Japanese petitioner without violating the treatys guarantee); Kolovrat, supra, at 192, and n. 6 (sustaining Yugoslavians claim against enforcement of Oregon inheritance law limiting their right to inherit, when United States-Serbia Treaty promised that [i]n all that concerns the right of acquiring, possessing or disposing of every kind of property citizens of [each country in the other] shall enjoy the rights which the respective laws grant in each of these states to the subjects of the most favored nation ).
Likewise, the United States acknowledges with approval that other provisions of the Vienna Convention, which relate to consular privileges and immunities, have been the source of judicially enforced individual rights. See Brief for United States as Amicus Curiae 26, n. 7 (citing Risk v. Halvorsen, 936 F. 2d 393, 397 (CA9 1991) (deciding whether Article 43 of the Vienna Convention defeated jurisdiction under 28 U. S. C. §1351 over defendant consular officials), and Gerritsen v. de la Madrid Hurtado, 819 F. 2d 1511, 15151516 (CA9 1997) (same)). Although Article 43 is phrased in terms of courts jurisdiction, its violations could theoretically also be vindicated exclusively in political and diplomatic processes, but have not been. See Art. 43(1), 21 U. S. T., at 104 (Consular officers and consular employees shall not be amenable to the jurisdiction of the judicial or administrative authorities of the receiving State in respect of acts performed in the exercise of consular functions); see also Kolovrat, supra, at 193; Hauenstein v. Lynham, 100 U. S. 483, 487 (1880).
There are plausible arguments for the Governments construction of Article 36. See generally Choctaw Nation v. United States, 318 U. S. 423, 431432 (1943) (looking to extrinsic sources for treaty interpretation). The preamble to the Vienna Convention, for example, states that the purpose of such privileges and immunities [contained in the treaty] is not to benefit individuals but to ensure the efficient performance of functions by consular posts on behalf of their respective States. 21 U. S. T., at 79. Moreover, State Department and congressional statements contemporaneous with the treatys ratification say or indicate that the Convention would not require significant departures from existing practice. See United States v. Li, 206 F. 3d 56, 6465 (CA1 2000); but see id., at 7375 (Torruella, C. J., concurring in part and dissenting in part). The United States interprets such statements to mean that the political branches did not contemplate a role for the treaty in ordinary criminal proceedings. See Brief for Uni