(Slip Opinion)              OCTOBER TERM, 2017                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

 ANIMAL SCIENCE PRODUCTS, INC., ET AL. v. HEBEI
   WELCOME PHARMACEUTICAL CO. LTD. ET AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                 THE SECOND CIRCUIT

      No. 16–1220.      Argued April 24, 2018—Decided June 14, 2018
Petitioners, U. S.-based purchasers of vitamin C (U. S. purchasers),
  filed a class-action suit, alleging that four Chinese corporations that
  manufacture and export the nutrient (Chinese sellers), including the
  two respondents here, had agreed to fix the price and quantity of vit-
  amin C exported to the United States, in violation of §1 of the Sher-
  man Act. The Chinese sellers moved to dismiss the complaint on the
  ground that Chinese law required them to fix the price and quantity
  of vitamin C exports, thus shielding them from liability under U. S.
  antitrust law. The Ministry of Commerce of the People’s Republic of
  China (Ministry) filed an amicus brief in support of the motion, ex-
  plaining that it is the administrative authority authorized to regulate
  foreign trade, and stating that the alleged conspiracy in restraint of
  trade was actually a pricing regime mandated by the Chinese Gov-
  ernment. The U. S. purchasers countered that the Ministry had
  identified no law or regulation ordering the Chinese sellers’ price
  agreement, highlighted a publication announcing that the Chinese
  sellers had agreed to control the quantity and rate of exports without
  government intervention, and presented supporting expert testimo-
  ny.
     The District Court denied the Chinese sellers’ motion in relevant
  part, concluding that it did not regard the Ministry’s statements as
  “conclusive,” particularly in light of the U. S. purchasers’ evidence.
  When the Chinese sellers subsequently moved for summary judg-
  ment, the Ministry submitted another statement, reiterating its
  stance, and the U. S. purchasers pointed to China’s statement to the
  World Trade Organization that it ended its export administration of
  vitamin C in 2002. The court denied this motion as well. The case
2             ANIMAL SCIENCE PRODUCTS, INC. v.
            HEBEI WELCOME PHARMACEUTICAL CO.
                          Syllabus

 was then tried to a jury, which returned a verdict for the U. S. pur-
 chasers.
    The Second Circuit reversed, holding that the District Court erred
 by denying the Chinese sellers’ motion to dismiss the complaint.
 When a foreign government whose law is in contention submits an of-
 ficial statement on the meaning and interpretation of its domestic
 law, the court concluded, federal courts are “bound to defer” to the
 foreign government’s construction of its own law, whenever that con-
 struction is “reasonable.” Inspecting only the Ministry’s brief and the
 sources cited therein, the court found the Ministry’s account of Chi-
 nese law “reasonable.”
Held: A federal court determining foreign law under Federal Rule of
 Civil Procedure 44.1 should accord respectful consideration to a for-
 eign government’s submission, but the court is not bound to accord
 conclusive effect to the foreign government’s statements.
    Rule 44.1 fundamentally changed the mode of determining foreign
 law in federal courts. Before adoption of the rule in 1966, a foreign
 nation’s laws had to be “proved as facts.” Talbot v. Seeman, 1 Cranch
 1, 38. Rule 44.1, in contrast, specifies that a court’s determination of
 foreign law “must be treated as a ruling on a question of law.” And in
 ascertaining foreign law, courts are not limited to materials submit-
 ted by the parties, but “may consider any relevant material or
 source.” Appellate review, as is true of domestic law determinations,
 is de novo. The purpose of these changes was to align, to the extent
 possible, the process for determining alien law and the process for de-
 termining domestic law.
    Neither Rule 44.1 nor any other rule or statute addresses the
 weight a federal court determining foreign law should give to the
 views presented by a foreign government. In the spirit of “interna-
 tional comity,” Société Nationale Industrielle Aérospatiale v. United
 States Dist. Court for Southern Dist. of Iowa, 482 U. S. 522, 543, and
 n. 27, a federal court should carefully consider a foreign state’s views
 about the meaning of its own laws. The appropriate weight in each
 case, however, will depend upon the circumstances; a federal court is
 neither bound to adopt the foreign government’s characterization nor
 required to ignore other relevant materials. No single formula or
 rule will fit all cases, but relevant considerations include the state-
 ment’s clarity, thoroughness, and support; its context and purpose;
 the transparency of the foreign legal system; the role and authority of
 the entity or official offering the statement; and the statement’s con-
 sistency with the foreign government’s past positions.
    Judged in this light, the Second Circuit’s unyielding rule is incon-
 sistent with Rule 44.1 and, tellingly, with this Court’s treatment of
 analogous submissions from States of the United States. If the rele-
                     Cite as: 585 U. S. ____ (2018)                    3

                               Syllabus

  vant state law is established by a decision of “the State’s highest
  court,” that decision is “binding on the federal courts,” Wainwright v.
  Goode, 464 U. S. 78, 84, but views of the State’s attorney general,
  while attracting “respectful consideration,” do not garner controlling
  weight, Arizonans for Official English v. Arizona, 520 U. S. 43, 76–
  77, n. 30. Furthermore, because the Second Circuit riveted its atten-
  tion on the Ministry’s submission, it did not address evidence submit-
  ted by the U. S. purchasers. The court also misperceived the pre-
  Rule 44.1 decision of United States v. Pink, 315 U. S. 203. Under the
  particular circumstances of that case, this Court found conclusive a
  declaration from the government of the Russian Socialist Federal So-
  viet Republic on the extraterritorial effect of a decree nationalizing
  assets: The declaration was obtained by the United States through of-
  ficial “diplomatic channels,” id., at 218; there was no indication that
  the declaration was inconsistent with the Russian Government’s past
  statements; and the declaration was consistent with expert evidence
  in point.
     The Second Circuit expressed concern about reciprocity, but the
  United States has not historically argued that foreign courts are
  bound to accept its characterizations or precluded from considering
  other relevant sources. International practice is also inconsistent
  with the Second Circuit’s rigid rule. Pp. 7–12.
837 F. 3d 175, vacated and remanded.

  GINSBURG, J., delivered the opinion for a unanimous Court.
                       Cite as: 585 U. S. ____ (2018)                              1

                            Opinion of the Court

    NOTICE: This opinion is subject to formal revision before publication in the
    preliminary print of the United States Reports. Readers are requested to
    notify the Reporter of Decisions, Supreme Court of the United States, Wash-
    ington, D. C. 20543, of any typographical or other formal errors, in order
    that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                  _________________

                                  No. 16–1220
                                  _________________


     ANIMAL SCIENCE PRODUCTS, INC., ET AL.,
        PETITIONERS v. HEBEI WELCOME
        PHARMACEUTICAL CO. LTD., ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE SECOND CIRCUIT
                                [June 14, 2018]

  JUSTICE GINSBURG delivered the opinion of the Court.
  When foreign law is relevant to a case instituted in a
federal court, and the foreign government whose law is in
contention submits an official statement on the meaning
and interpretation of its domestic law, may the federal
court look beyond that official statement? The Court of
Appeals for the Second Circuit answered generally “no,”
ruling that federal courts are “bound to defer” to a foreign
government’s construction of its own law, whenever that
construction is “reasonable.” In re Vitamin C Antitrust
Litigation, 837 F. 3d 175, 189 (2016).
  We hold otherwise. A federal court should accord re-
spectful consideration to a foreign government’s submis-
sion, but is not bound to accord conclusive effect to the
foreign government’s statements. Instead, Federal Rule of
Civil Procedure 44.1 instructs that, in determining foreign
law, “the court may consider any relevant material or
source . . . whether or not submitted by a party.” As “[t]he
court’s determination must be treated as a ruling on a
question of law,” Fed. Rule Civ. Proc. 44.1, the court “may
2           ANIMAL SCIENCE PRODUCTS, INC. v.
          HEBEI WELCOME PHARMACEUTICAL CO.
                   Opinion of the Court

engage in its own research and consider any relevant
material thus found,” Advisory Committee’s 1966 Note on
Fed. Rule Civ. Proc. 44.1, 28 U. S. C. App., p. 892 (herein-
after Advisory Committee’s Note). Because the Second
Circuit ordered dismissal of this case on the ground that
the foreign government’s statements could not be gainsaid,
we vacate that court’s judgment and remand the case for
further consideration.
                              I
  Petitioners, U. S.-based purchasers of vitamin C (here-
inafter U. S. purchasers), filed a class-action suit against
four Chinese corporations that manufacture and export
the nutrient (hereinafter Chinese sellers). The U. S.
purchasers alleged that the Chinese sellers, two of whom
are respondents here, had agreed to fix the price and
quantity of vitamin C exported to the United States from
China, in violation of §1 of the Sherman Act, 15 U. S. C.
§1. More particularly, the U. S. purchasers stated that the
Chinese sellers had formed a cartel “facilitated by the
efforts of their trade association,” the Chamber of Com-
merce of Medicines and Health Products Importers and
Exporters (Chamber). Complaint in No. 1:05–CV–453,
Docket No. 1, ¶43. The Judicial Panel on Multidistrict
Litigation consolidated the instant case and related suits
for pretrial proceedings in the United States District
Court for the Eastern District of New York.
  The Chinese sellers moved to dismiss the U. S. pur-
chasers’ complaint on the ground that Chinese law required
them to fix the price and quantity of vitamin C exports.
Therefore, the Chinese sellers urged, they are shielded
from liability under U. S. antitrust law by the act of state
doctrine, the foreign sovereign compulsion doctrine, and
principles of international comity. The Ministry of Com-
merce of the People’s Republic of China (Ministry) filed a
brief as amicus curiae in support of the Chinese sellers’
                     Cite as: 585 U. S. ____ (2018)                     3

                          Opinion of the Court

motion. The Ministry’s brief stated that the Ministry is
“the highest administrative authority in China authorized
to regulate foreign trade,” App. to Pet. for Cert. 190a; that
the Chamber is “an entity under the Ministry’s direct and
active supervision” and is authorized to regulate vitamin
C exports, id., at 196a; and that the conspiracy in re-
straint of trade alleged by the U. S. purchasers was in fact
“a regulatory pricing regime mandated by the government
of China,” id., at 197a. 1
   In response, the U. S. purchasers disputed that Chinese
law required the Chinese sellers to engage in price fixing.
Among other things, the U. S. purchasers noted that the
Ministry had not identified any written law or regulation


——————
  1 The  Ministry told the District Court: For much of the 20th century,
China allowed only state-owned entities to export products. App. to
Pet. for Cert. 198a. When China started to allow private enterprises to
obtain export licenses, the Ministry established the Chamber to regu-
late exports under the Ministry’s authority and direction. Ibid.
  In 1997, the Ministry authorized the establishment of the Chamber’s
Vitamin C Subcommittee. Id., at 202a. That year, the Ministry prom-
ulgated a regulation authorizing and requiring the subcommittee to
limit the production of vitamin C for export and to set export prices.
Id., at 202a–204a. Under the regulation delineating this “Export
Licensing System,” the Ministry issued export licenses only to manufac-
turers whose export volume and price complied with the output quota
and price coordinated by the Vitamin C Subcommittee. Id., at 204a.
  In 2002, the Ministry replaced the Export Licensing System with a
“Verification and Chop System.” Id., at 208a. As set forth in a 2002
Ministry Notice, the Chamber itself—instead of the Ministry—would
inspect each export contract and certify its compliance with the coordi-
nated quotas and price by affixing a special seal, known as a “chop.”
Id., at 208a–209a. China’s Customs would allow export only if the
exporter presented its contract bearing the Chamber’s “chop.” Id., at
209a. According to the Ministry, it was implicit in this arrangement
that vitamin C exporters would remain under an obligation to fix prices
and volumes. Id., at 208a.
  The effect of China’s regime on the Chinese sellers’ liability under the
Sherman Act, we note, is not an issue before the Court today.
4             ANIMAL SCIENCE PRODUCTS, INC. v.
            HEBEI WELCOME PHARMACEUTICAL CO.
                     Opinion of the Court

expressly ordering the Chinese sellers’ price agreement. 2
They also highlighted a Chamber announcement that the
manufacturers “were able to reach a self-regulated agree-
ment . . . whereby they would voluntarily control the
quantity and pace of exports . . . without any government
intervention.” App. 109. In addition, the U. S. purchasers
presented expert testimony that the Chinese Govern-
ment’s authorization of a Vitamin C Subcommittee within
the Chamber did not necessarily mean that the subcom-
mittee’s price fixing was mandated by law.
  The District Court denied the Chinese sellers’ motion to
dismiss the complaint in relevant part. In re Vitamin C
Antitrust Litigation, 584 F. Supp. 2d 546, 559 (EDNY
2008). That court acknowledged that the Ministry’s ami-
cus brief was “entitled to substantial deference.” Id., at
557. The court, however, did not regard the Ministry’s
statements as “conclusive,” emphasizing particularly that
the U. S. purchasers had submitted evidence suggesting
that the price fixing was voluntary. Ibid. The record, the
District Court determined, was “too ambiguous to foreclose
further inquiry into the voluntariness of [the Chinese
sellers’] actions.” Id., at 559.
  After further discovery, focused on whether Chinese law
compelled the Chinese sellers to enter into a price-fixing
agreement, the Chinese sellers moved for summary judg-
ment. See In re Vitamin C Antitrust Litigation, 810
F. Supp. 2d 522, 525–526 (EDNY 2011). The Ministry
——————
  2 The complaint, the U. S. purchasers emphasized, was directed only

at conduct occurring after December 2001. As they understood the
Ministry’s 2002 Notice, see supra, at 3, n. 1, vitamin C exporters could
have lawfully opted out of price fixing. Beyond that, the Vitamin C
Subcommittee had replaced its 1997 Charter with a new 2002 Charter,
App. 182–197, which eliminated the 1997 Charter’s requirement that
subcommittee members “[s]trictly execute” the “coordinated price” set
by the Chamber, compare id., at 85, with id., at 185, and granted
members an express “[r]igh[t]” to “freely resign from the Subcommit-
tee,” id., at 186.
                 Cite as: 585 U. S. ____ (2018)            5

                     Opinion of the Court

submitted an additional statement, reiterating that “the
Ministry specifically charged the Chamber . . . with the
authority and responsibility . . . for regulating, through
consultation, the price of vitamin C manufactured for
export.” App. 133. The Chinese sellers tendered expert
testimony in accord with the Ministry’s account, which
stressed that the Ministry’s “interpretation of its own
regulations and policies carries decisive weight under
Chinese law.” Id., at 142. The U. S. purchasers, in re-
sponse, cited further materials supporting their opposing
view, including China’s statement to the World Trade
Organization (WTO) that it “gave up export administra-
tion of . . . vitamin C” in 2002. 810 F. Supp. 2d, at 532
(internal quotation marks omitted). Denying the Chinese
sellers’ motion for summary judgment, the District Court
held that Chinese law did not require the sellers to fix the
price or quantity of vitamin C exports. Id., at 525.
   The case was then tried to a jury, which returned a
verdict for the U. S. purchasers. The jury found that the
Chinese sellers had agreed to fix the prices and quantities
of vitamin C exports, see App. to Pet. for Cert. 276a–279a,
and further found that the Chinese sellers were not “actu-
ally compelled” by China to enter into those agreements,
id., at 278a. In accord with the jury’s verdict, the District
Court entered judgment for the U. S. purchasers, award-
ing some $147 million in treble damages and enjoining the
Chinese sellers from further violations of the Sherman
Act.
   The Court of Appeals for the Second Circuit reversed,
holding that the District Court erred in denying the Chi-
nese sellers’ motion to dismiss the complaint. In re Vita-
min C Antitrust Litigation, 837 F. 3d 175, 178, 195–196
(2016). The Court of Appeals determined that the propri-
ety of dismissal hinged on whether the Chinese sellers
could adhere to both Chinese law and U. S. antitrust law.
See id., at 186. That question, in turn, depended on “the
6           ANIMAL SCIENCE PRODUCTS, INC. v.
          HEBEI WELCOME PHARMACEUTICAL CO.
                   Opinion of the Court

amount of deference” owed to the Ministry’s characteriza-
tion of Chinese law. Ibid. Cognizant of “competing au-
thority” on this question, ibid., the Court of Appeals set-
tled on a highly deferential rule: “[W]hen a foreign
government, acting through counsel or otherwise, directly
participates in U. S. court proceedings by providing a
[statement] regarding the construction and effect of [the
foreign government’s] laws and regulations, which is
reasonable under the circumstances presented, a U. S.
court is bound to defer to those statements,” id., at 189.
The appeals court “note[d] that[,] if the Chinese Govern-
ment had not appeared in this litigation, the [D]istrict
[C]ourt’s careful and thorough treatment of the evidence
before it in analyzing what Chinese law required at both
the motion to dismiss and summary judgment stages
would have been entirely appropriate.” Id., at 191, n. 10.
   Applying its highly deferential rule, the Court of Ap-
peals concluded that the Ministry’s account of Chinese law
was “reasonable.” In so concluding, the Court of Appeals
inspected only the Ministry’s brief and sources cited therein.
Id., at 189–190. Because it thought that “a U. S. court
[must] not embark on a challenge to a foreign govern-
ment’s official representation,” id., at 189, the Court of
Appeals disregarded the submissions made by the U. S.
purchasers casting doubt on the Ministry’s account of
Chinese law, id., at 189–190. Based solely on the Minis-
try’s statements, the Court of Appeals held that “Chinese
law required [the Chinese sellers] to engage in activities in
China that constituted antitrust violations here in the
United States.” Ibid.
   We granted certiorari to resolve a Circuit conflict over
this question: Is a federal court determining foreign law
under Rule 44.1 required to treat as conclusive a submis-
sion from the foreign government describing its own law?
                     Cite as: 585 U. S. ____ (2018)                   7

                         Opinion of the Court

583 U. S. ___ (2018). 3
                             II
  At common law, the content of foreign law relevant to a
dispute was treated “as a question of fact.” Miller, Federal
Rule 44.1 and the “Fact” Approach to Determining Foreign
Law: Death Knell for a Die-Hard Doctrine, 65 Mich.
L. Rev. 613, 617–619 (1967) (Miller). In 1801, this Court
endorsed the common-law rule, instructing that “the laws
of a foreign nation” must be “proved as facts.” Talbot v.
Seeman, 1 Cranch 1, 38 (1801); see, e.g., Church v. Hub-
bart, 2 Cranch 187, 236 (1804) (“Foreign laws are well
understood to be facts.”). Ranking questions of foreign law
as questions of fact, however, “had a number of undesir-
able practical consequences.” 9A C. Wright & A. Miller,
Federal Practice and Procedure §2441, p. 324 (3d ed. 2008)
(Wright & Miller). Foreign law “had to be raised in the
pleadings” and proved “in accordance with the rules of
evidence.” Ibid. Appellate review was deferential and
limited to the record made in the trial court. Ibid.; see
also Miller 623.
  Federal Rule of Civil Procedure 44.1, adopted in 1966,
fundamentally changed the mode of determining foreign
law in federal courts. The Rule specifies that a court’s

——————
  3 Compare In re Vitamin C Antitrust Litigation, 837 F. 3d 175 (CA2

2016) (case below), with In re Oil Spill by Amoco Cadiz, 954 F. 2d 1279,
1311–1313 (CA7 1992) (adopting French Government’s interpretation
of French law, but only after considering all of the circumstances,
including the French Government’s statements in other contexts);
United States v. McNab, 331 F. 3d 1228, 1239–1242 (CA11 2003)
(noting Honduran Government’s shift in position on the question of
Honduran law and determining that the original position stated the
proper interpretation); McKesson HBOC, Inc. v. Islamic Republic of
Iran, 271 F. 3d 1101, 1108–1109 (CADC 2001), vacated in part on other
grounds, 320 F. 3d 280 (CADC 2003) (declining to adopt the view of
Iranian law advanced by Iranian Government because it was not
supported by the affidavits submitted by Iran’s experts).
8             ANIMAL SCIENCE PRODUCTS, INC. v.
            HEBEI WELCOME PHARMACEUTICAL CO.
                     Opinion of the Court

determination of foreign law “must be treated as a ruling
on a question of law,” rather than as a finding of fact. 4
Correspondingly, in ascertaining foreign law, courts are
not limited to materials submitted by the parties; instead,
they “may consider any relevant material or source . . . ,
whether or not . . . admissible under the Federal Rules of
Evidence.” Ibid. Appellate review, as is true of domestic
law determinations, is de novo. Advisory Committee’s
Note, at 892. Rule 44.1 frees courts “to reexamine and
amplify material . . . presented by counsel in partisan
fashion or in insufficient detail.” Ibid. The “obvious”
purpose of the changes Rule 44.1 ordered was “to make
the process of determining alien law identical with the
method of ascertaining domestic law to the extent that it
is possible to do so.” Wright & Miller §2444, at 338–342.
   Federal courts deciding questions of foreign law under
Rule 44.1 are sometimes provided with the views of the
relevant foreign government, as they were in this case
through the amicus brief of the Ministry. See supra, at 2–
3. As the Court of Appeals correctly observed, Rule 44.1
does not address the weight a federal court determining
foreign law should give to the views presented by the
foreign government. See 837 F. 3d, at 187. Nor does any
other rule or statute. In the spirit of “international comity,”
Société Nationale Industrielle Aérospatiale v. United
States Dist. Court for Southern Dist. of Iowa, 482 U. S.
522, 543, and n. 27 (1987), a federal court should carefully
consider a foreign state’s views about the meaning of its
own laws. See United States v. McNab, 331 F. 3d 1228,
1241 (CA11 2003); cf. Bodum USA, Inc. v. La Cafetière,
Inc., 621 F. 3d 624, 638–639 (CA7 2010) (Wood, J., concur-
ring). But the appropriate weight in each case will depend
——————
  4 Federal Rule of Criminal Procedure 26.1 establishes “substantially

the same” rule for criminal cases. Advisory Committee’s 1966 Note on
Fed. Rule Crim. Proc. 26.1, 18 U. S. C. App., p. 709.
                 Cite as: 585 U. S. ____ (2018)            9

                     Opinion of the Court

upon the circumstances; a federal court is neither bound to
adopt the foreign government’s characterization nor re-
quired to ignore other relevant materials. When a foreign
government makes conflicting statements, see supra, at 5,
or, as here, offers an account in the context of litigation,
there may be cause for caution in evaluating the foreign
government’s submission.
   Given the world’s many and diverse legal systems, and
the range of circumstances in which a foreign govern-
ment’s views may be presented, no single formula or rule
will fit all cases in which a foreign government describes
its own law. Relevant considerations include the state-
ment’s clarity, thoroughness, and support; its context and
purpose; the transparency of the foreign legal system; the
role and authority of the entity or official offering the
statement; and the statement’s consistency with the for-
eign government’s past positions.
   Judged in this light, the Court of Appeals erred in deem-
ing the Ministry’s submission binding, so long as facially
reasonable. That unyielding rule is inconsistent with Rule
44.1 (determination of an issue of foreign law “must be
treated as a ruling on a question of law”; court may con-
sider “any relevant material or source”) and, tellingly,
with this Court’s treatment of analogous submissions from
States of the United States. If the relevant state law is
established by a decision of “the State’s highest court,”
that decision is “binding on the federal courts.” Wain-
wright v. Goode, 464 U. S. 78, 84 (1983) (per curiam); see
Mullaney v. Wilbur, 421 U. S. 684, 691 (1975). But views
of the State’s attorney general, while attracting “respectful
consideration,” do not garner controlling weight. Arizo-
nans for Official English v. Arizona, 520 U. S. 43, 76–77,
n. 30 (1997); see, e.g., Virginia v. American Booksellers
Assn., Inc., 484 U. S. 383, 393–396 (1988). Furthermore,
because the Court of Appeals riveted its attention on the
Ministry’s submission, it did not address other evidence,
10            ANIMAL SCIENCE PRODUCTS, INC. v.
            HEBEI WELCOME PHARMACEUTICAL CO.
                     Opinion of the Court

including, for example, China’s statement to the WTO that
China had “g[i]ve[n] up export administration . . . of vita-
min C” at the end of 2001. 810 F. Supp. 2d, at 532 (inter-
nal quotation marks omitted). 5
  The Court of Appeals also misperceived this Court’s
decision in United States v. Pink, 315 U. S. 203 (1942).
See 837 F. 3d, at 186–187, 189. Pink, properly compre-
hended, is not compelling authority for the attribution of
controlling weight to the Ministry’s brief. We note, first,
that Pink was a pre-Rule 44.1 decision. Second, Pink
arose in unusual circumstances. Pink was an action
brought by the United States to recover assets of the U. S.
branch of a Russian insurance company that had been
nationalized in 1918, after the Russian revolution. 315
U. S., at 210–211. In 1933, the Soviet Government as-
signed the nationalized assets located in this country to
the United States. Id., at 211–212. The disposition of the
case turned on the extraterritorial effect of the nationali-
zation decree—specifically, whether the decree reached
assets of the Russian insurance company located in the
United States, or was instead limited to property in Rus-
sia. Id., at 213–215, 217. To support the position that the
decree reached all of the company’s assets, the United
States obtained an “official declaration of the Commissar-
iat for Justice” of the Russian Socialist Federal Soviet
Republic. Id., at 218. The declaration certified that the
nationalization decree reached “the funds and property of
former insurance companies . . . irrespective of whether
[they were] situated within the territorial limits of [Rus-
——————
  5 The Court of Appeals additionally mischaracterized the Ministry’s

brief as a “sworn evidentiary proffer.” 837 F. 3d, at 189. In so describ-
ing the Ministry’s submission, the Court of Appeals overlooked that a
court’s resolution of an issue of foreign law “must be treated as a ruling
on a question of law.” Fed. Rule Civ. Proc. 44.1. The Ministry’s brief,
while a probative source for resolving the legal question at hand, was
not an attestation to facts.
                    Cite as: 585 U. S. ____ (2018)                  11

                         Opinion of the Court

sia] or abroad.” Id., at 220 (internal quotation marks
omitted). This Court determined that “the evidence sup-
ported [a] finding” that “the Commissariat for Justice
ha[d] power to interpret existing Russian law.” Ibid.
“That being true,” the Court concluded, the “official decla-
ration [wa]s conclusive so far as the intended extraterrito-
rial effect of the Russian decree [wa]s concerned.” Ibid.
   This Court’s treatment of the Commissariat’s submis-
sion as conclusive rested on a document obtained by the
United States, through official “diplomatic channels.” Id.,
at 218. There was no indication that the declaration was
inconsistent with the Soviet Union’s past statements.
Indeed, the Court emphasized that the declaration was
consistent with expert evidence in point. See ibid. That
the Commissariat’s declaration was deemed “conclusive”
in the circumstances Pink presented scarcely suggests
that all submissions by a foreign government are entitled
to the same weight.
   The Court of Appeals also reasoned that a foreign gov-
ernment’s characterization of its own laws should be
afforded “the same respect and treatment that we would
expect our government to receive in comparable matters.”
837 F. 3d, at 189. The concern for reciprocity is sound, but
it does not warrant the Court of Appeals’ judgment. In-
deed, the United States, historically, has not argued that
foreign courts are bound to accept its characterizations or
precluded from considering other relevant sources. 6
   The understanding that a government’s expressed view
——————
  6 The  Chinese sellers assert, see Supp. Brief for Respondents 7–8,
that the United States sought a greater degree of deference in a 2002
submission to a World Trade Organization panel. In fact, the submis-
sion acknowledged that “the Panel is not bound to accept the interpre-
tation [of U. S. law] presented by the United States.” Brief for United
States as Amicus Curiae 29, n. 6 (quoting Second Written Submission
of the United States of America, United States—Section 129(c)(1) of the
Uruguay Round Agreements Act, WT/DS221 ¶11 (Mar. 8, 2002)).
12           ANIMAL SCIENCE PRODUCTS, INC. v.
           HEBEI WELCOME PHARMACEUTICAL CO.
                    Opinion of the Court

of its own law is ordinarily entitled to substantial but not
conclusive weight is also consistent with two international
treaties that establish formal mechanisms by which one
government may obtain from another an official statement
characterizing its laws. Those treaties specify that “[t]he
information given in the reply shall not bind the judicial
authority from which the request emanated.” European
Convention on Information on Foreign Law, Art. 8, June 7,
1968, 720 U. N. T. S. 154; see Inter-American Convention
on Proof of and Information on Foreign Law, Art. 6, May
8, 1979, O. A. S. T. S. 1439 U. N. T. S. 111 (similar). Al-
though the United States is not a party to those treaties,
they reflect an international practice inconsistent with the
Court of Appeals’ “binding, if reasonable” resolution.
                         *    *     *
   Because the Court of Appeals concluded that the Dis-
trict Court was bound to defer to the Ministry’s brief, the
court did not consider the shortcomings the District Court
identified in the Ministry’s position or other aspects of “the
[D]istrict [C]ourt’s careful and thorough treatment of the
evidence before it.” 837 F. 3d, at 191, n. 10. The correct
interpretation of Chinese law is not before this Court, and
we take no position on it. But the materials identified by
the District Court were at least relevant to the weight the
Ministry’s submissions should receive and to the question
whether Chinese law required the Chinese sellers’ con-
duct. We therefore vacate the judgment of the Court of
Appeals and remand the case for renewed consideration
consistent with this opinion.
                                              It is so ordered.
