DEPARTMENTOFDEFENSE LAW OFWARMANUAL JUNE2015

In addition to treaties, domestic statutes have also been construed not to violate
international law, including the law of war, if any other construction remains possible. 28 Certain
domestic statutes have been interpreted not to apply to situations addressed by the law of war
because such intention was not made clear and unequivocal. 29
1.3.2.3 Using the Law of War to Determine the Content of General Standards if
Applied to Armed Conflict. Another way in which the law of war has been applied as lex
specialis is to determine the content of a more general standard with respect to the situation of
armed conflict. For example, the law of war has been used to inform the content of general
authorizations to conduct military operations. 30
United States of America understands that nothing in the Convention precludes any State Party to the Convention
from conducting any legitimate activity against any lawful target in accordance with the law of armed conflict.”).
28 The Charming Betsy, 6 U.S. 64, 118 (1804) (Marshall, C.J.) (“It has also been observed that an act of Congress
ought never to be construed to violate the law of nations if any other possible construction remains, and
consequently can never be construed to violate neutral rights or to affect neutral commerce further than is warranted
by the law of nations as understood in this country. These principles are believed to be correct, and they ought to be
kept in view in construing the act now under consideration.”).
29 See, e.g., Walter Dellinger, Assistant Attorney General, United States Assistance to Countries that Shoot Down
Civil Aircraft Involved in Drug Trafficking, Jul. 14, 1994, 18 OPINIONS OF THE OFFICE OF LEGAL COUNSEL 148, 163-
64 (“Specifically, we believe that the section would not apply to the actions of United States military forces acting
on behalf of the United States during a state of hostilities. As discussed above, § 32(b)(2) was intended to
implement the United States’s obligations under the Montreal Convention. That Convention does not appear to
apply to acts of armed forces that are otherwise governed by the laws of armed conflict. … We do not think that
§ 32(b)(2) should be construed to have the surprising and almost certainly unintended effect of criminalizing actions
by military personnel that are lawful under international law and the laws of armed conflict. We note specifically
that the application of § 32(b)(2) to acts of United States military personnel in a state of hostilities could readily lead
to absurdities: for example, it could mean in some circumstances that military personnel would not be able to
engage in reasonable self-defense without subjecting themselves to the risk of criminal prosecution. Unless
Congress by a clear and unequivocal statement declares otherwise, § 32(b)(2) should be construed to avoid such
outcomes. Thus, we do not think the statute, as written, should apply to such incidents as the downing on July 3,
1988 of Iran Air Flight 655 by the United States Navy cruiser Vincennes.”); France Biddle, Attorney General,
Procurements by Commanding Generals in Foreign Theaters of Operations, Nov. 12, 1942, 40 OPINIONS OF THE
ATTORNEY GENERAL 250, 253 (1949) (“The statutes in question do not expressly declare that their provisions are
inapplicable to foreign theaters of operations. But there are conclusive reasons for inferring that the Congress did
not intend them to apply to such theaters. The Supreme Court has long recognized that the power to conduct
military campaigns includes power to procure needed supplies in theaters of operations by whatever methods are
dictated by military necessity. Property may be taken summarily, even from a citizen, if military exigencies make
its seizure reasonably appear to be necessary. It is unthinkable that the Congress attempted, by statutory restrictions,
to abrogate this rule of military necessity, to handicap commanding generals waging war on foreign soil, to limit or
encroach upon the power of the President as Commander in Chief to conduct, through his subordinates, military
campaigns abroad.”) (internal citations omitted).
30 Hamdi v. Rumsfeld, 542 U.S. 507, 519 (2004) (plurality) (“In light of these principles, it is of no moment that the
AUMF does not use specific language of detention. Because detention to prevent a combatant’s return to the
battlefield is a fundamental incident of waging war, in permitting the use of ‘necessary and appropriate force,’
Congress has clearly and unmistakably authorized detention in the narrow circumstances considered here.”). See
also In re Guantanamo Bay Litigation, Respondents’ Memorandum Regarding the Government’s Detention
Authority Relative to Detainees Held at Guantanamo Bay, Misc. No. 08-442, 4 (D.D.C., Mar. 13, 2009) (“The
United States bases its detention authority as to such persons on the Authorization for the Use of Military Force
(‘AUMF’), Pub. L. 107-40, 115 Stat. 224 (2001). The detention authority conferred by the AUMF is necessarily
informed by principles of the laws of war.”).
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