Related Rule
United States of America
Practice Relating to Rule 65. Perfidy
The US Field Manual (1956) states:
The line of demarcation between legitimate ruses and forbidden acts of perfidy is sometimes indistinct … It would be an improper practice to secure an advantage of the enemy by deliberate lying or misleading conduct which involves a breach of faith, or when there is a moral obligation to speak the truth …
Treacherous or perfidious conduct in war is forbidden because it destroys the basis for a restoration of peace short of the complete annihilation of one belligerent by the other. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 50.
The US Air Force Pamphlet (1976) states:
Perfidy or treachery involves acts inviting the confidence of the adversary that he is entitled to protection or is obliged to accord protection under international law, combined with intent to betray that confidence … Like ruses perfidy involves simulation, but it aims at falsely creating a situation in which the adversary, under international law, feels obliged to take action or abstain from taking action, or because of protection under international law neglects to take precautions which are otherwise necessary … In addition, perfidy tends to destroy the basis for restoration of peace and causes the conflict to degenerate into savagery. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-3(a).
The US Instructor’s Guide (1985) notes: “The law of war prohibits treacherous acts.” 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 8.
The US Naval Handbook (1995) states:
The use of unlawful deceptions is called “perfidy”. Acts of perfidy are deceptions designed to invite the confidence of the enemy to lead him to believe that he is entitled to, or is obliged to accord, protected status under the law of armed conflict, with the intent to betray that confidence. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.1.2.
The US Naval Handbook (2007) states:
The use of unlawful deceptions is called “perfidy”. Acts of perfidy are deceptions designed to invite the confidence of the enemy to lead him to believe that he is entitled to, or is obliged to accord, protected status under the law of armed conflict, with the intent to betray that confidence. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.1.2.
In 1991, in response to an ICRC memorandum on the applicability of IHL in the Gulf region, the US Department of the Army stated that its practice was consistent with the definition and prohibition of perfidy contained in Article 37 of the 1977 Additional Protocol I. 
United States, Letter from the Department of the Army to the legal adviser of the US Army forces deployed in the Gulf region, 11 January 1991, § 8(J), Report on US Practice, 1997, Chapter 2.8.
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated:
Perfidy is prohibited by the law of war. Perfidy is defined in Article 37(1) of [the 1977 Additional Protocol I] as:
Acts inviting the confidence of an adversary to lead him to believe that he is entitled to, or is obliged to accord, protection under the law [of war], with intent to betray that confidence …
Perfidious acts are prohibited on the basis that perfidy may damage mutual respect for the law of war, may lead to unnecessary escalation of the conflict, may result in the injury or death of enemy forces legitimately attempting to surrender or discharging their humanitarian duties, or may impede the restoration of peace …
However, there does not appear to have been any centrally directed Iraqi policy to carry out acts of perfidy. The fundamental principles of the law of war applied to Coalition and Iraqi forces throughout the war. 
United States, Department of Defense, Final Report to Congress on the Conduct of the Persian Gulf War, 10 April 1992, Appendix O, The Role of the Law of War, ILM, Vol. 31, 1992, p. 632.
The US Field Manual (1956) states:
It is especially forbidden to kill or wound treacherously individuals belonging to the hostile nation or army …
[Article 23(b) of the 1907 Hague Regulations] is construed as prohibiting assassination, proscription, or outlawry of an enemy, or putting a price upon an enemy’s head, as well as offering a reward for an enemy “dead or alive”. It does not, however, preclude attacks on individual soldiers or officers of the enemy whether in the zone of hostilities, occupied territory, or elsewhere. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 31.
The US Air Force Pamphlet (1976) provides: “It is especially forbidden … to kill or wound treacherously individuals belonging to the hostile nation or army.” 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-2.
The Pamphlet also states:
Article 23(b) [of the 1907] Hague Regulations … prohibits the killing or wounding treacherously of individuals belonging to a hostile nation or army, whether they are combatants or civilians. This article has been construed as prohibiting assassination, proscription, or outlawry of an enemy, or putting a price upon an enemy’s head, as well as offering a reward for an enemy “dead or alive”. Obviously, it does not preclude lawful attacks by lawful combatants on individual soldiers or officers of the enemy. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-6(d).
The US Manual for Military Commissions (2007), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
USING TREACHERY OR PERFIDY.
a. Text. “Any person subject to this chapter who, after inviting the confidence or belief of one or more persons that they were entitled to, or obliged to accord, protection under the law of war, intentionally makes use of that confidence or belief in killing, injuring, or capturing such person or persons shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct.”
b. Elements.
(1) The accused invited the confidence or belief of one or more persons that they were entitled, or obliged to accord, protection under the law of war;
(2) The accused intended to betray that confidence or belief;
(3) The accused killed, injured or captured one or more persons;
(4) The accused made use of that confidence or belief in killing, injuring or capturing such person or persons; and
(5) The conduct took place in the context of and was associated with armed conflict.
c. Comment.
(1) Ruses of war are legitimate so long as they do not involve treachery or perfidy on the part of the belligerent resorting to them. They are, however, forbidden if they contravene any generally accepted rule.
(2) The line of demarcation between legitimate ruses and forbidden acts of perfidy is sometimes indistinct, but the following examples indicate the correct principles. It would be an improper practice to secure an advantage of the enemy by deliberate lying or misleading conduct which involves a breach of faith, or when there is a moral obligation to speak the truth. For example, it is improper to feign surrender so as to secure an advantage over the opposing belligerent thereby. So similarly, to broadcast to the enemy that an armistice had been agreed upon when such is not the case would be treacherous. On the other hand, it is a perfectly proper ruse to summon a force to surrender on the ground that it is surrounded and thereby induce such surrender with a small force.
(3) Treacherous or perfidious conduct in war is forbidden because it destroys the basis for a restoration of peace short of the complete annihilation of one belligerent by the other.
(4) One may commit an act of treachery or perfidy by, for example, feigning an intent to negotiate under a flag of truce or a surrender or feigning incapacitation by wounds or sickness or feigning a civilian, non-combatant status or feigning a protected status by the use of signs, emblems, or uniforms of the United Nations or a neutral State or a State not party to the conflict.
d. Maximum punishment. Death, if the death of any person occurs as a result of the improper use of the treachery or perfidy. Otherwise, confinement for life.  
United States, Manual for Military Commissions, published in implementation of the Military Commissions Act of 2006, 10 U.S.C. §§ 948a, et seq., 18 January 2007, Part IV, § 6(17), pp. IV-13 and IV-14.
The US Naval Handbook (2007) states:
Improperly using protective signs, signals, and symbols … to injure, kill, or capture the enemy is an act of perfidy. Such acts are prohibited because they undermine the effectiveness of protective signs, signals, and symbols and thereby jeopardize the safety of noncombatants and the immunity of protected structures and activities. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.2.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
USING TREACHERY OR PERFIDY.
a. Text. “Any person subject to this chapter who, after inviting the confidence or belief of one or more persons that they were entitled to, or obliged to accord, protection under the law of war, intentionally makes use of that confidence or belief in killing, injuring, or capturing such person or persons shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct.”
b. Elements.
(1) The accused invited the confidence or belief of one or more persons that they were entitled, or obliged to accord, protection under the law of war;
(2) The accused intended to betray that confidence or belief;
(3) The accused killed, injured or captured one or more persons;
(4) The accused made use of that confidence or belief in killing, injuring or capturing such person or persons; and
(5) The conduct took place in the context of and was associated with hostilities.
c. Comment.
(1) Ruses of war are legitimate so long as they do not involve treachery or perfidy on the part of the belligerent resorting to them. They are, however, forbidden if they contravene any generally accepted rule.
(2) The line of demarcation between legitimate ruses and forbidden acts of perfidy is sometimes indistinct, but the following examples indicate the correct principles. It would be an improper practice to secure an advantage of the enemy by deliberate lying or misleading conduct which involves a breach of faith, or when there is a moral obligation to speak the truth. For example, it is improper to feign surrender so as to secure an advantage over the opposing belligerent thereby. So similarly, to broadcast to the enemy that an armistice had been agreed upon when such is not the case would be treacherous. On the other hand, it is a perfectly proper ruse to summon a force to surrender on the ground that it is surrounded and thereby induce such surrender with a small force.
(3) Treacherous or perfidious conduct in war is forbidden because it destroys the basis for a restoration of peace short of the complete annihilation of one belligerent by the other.
(4) One may commit an act of treachery or perfidy by, for example, feigning an intent to negotiate under a flag of truce or a surrender or feigning incapacitation by wounds or sickness or feigning a civilian, non-combatant status or feigning a protected status by the use of signs, emblems, or uniforms of the United Nations or a neutral State or a State not party to the conflict.
d. Maximum punishment. Death, if the death of any person occurs as a result of the improper use of the treachery or perfidy. Otherwise, confinement for life. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17), pp. IV-14 and IV-15.
Under the US War Crimes Act (1996), violations of Article 23(b) of the 1907 Hague Regulations are war crimes. 
United States, War Crimes Act, 1996, Section 2441(c)(2).
The US Military Commissions Act (2006), passed by Congress following the Supreme Court’s decision in Hamdan v. Rumsfeld in 2006, amends Title 10 of the United States Code as follows:
§ 950v. Crimes triable by military commissions
“ …
“(b) OFFENSES.—The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(17) USING TREACHERY OR PERFIDY.—Any person subject to this chapter who, after inviting the confidence or belief of one or more persons that they were entitled to, or obliged to accord, protection under the law of war, intentionally makes use of that confidence or belief in killing, injuring, or capturing such person or persons shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2006, Public Law 109-366, Chapter 47A of Title 10 of the United States Code, 17 October 2006, p. 120 Stat. 2629, § 950v(b)(17).
The US Military Commissions Act (2009) amends Chapter 47A of Title 10 of the United States Code as follows:
§ 950t. Crimes triable by military commission
“The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(17) USING TREACHERY OR PERFIDY.—Any person subject to this chapter who, after inviting the confidence or belief of one or more persons that they were entitled to, or obliged to accord, protection under the law of war, intentionally makes use of that confidence or belief in killing, injuring, or capturing such person or persons shall be punished, if death results to one or more of the victims, by death or such other punishment as a military commission under this chapter may direct, and, if death does not result to any of the victims, by such punishment, other than death, as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2009, § 950t(17).
In its Country Reports on Human Rights Practices for 1996, in a section entitled “Use of Excessive Force and Violations of Humanitarian Law in Internal Conflicts”, the US Department of State noted that, in Uganda, “newspapers reported that [a rebel leader] offered bounties for the killing of prominent Ugandan military personnel, including the Minister of State for Defence”. 
United States, Department of State, Country Reports on Human Rights Practices for 1996, United States Government Printing Office, Washington D.C., 30 January 1997.
The US Presidential Executive Order 12333 of 1981 provides: “No person employed by or acting on behalf of the United States Government shall engage in, or conspire to engage in, assassination.” 
United States, Executive Order 12333, 4 December 1981, CFR, 1981 Comp. (1982), p. 213.
In 1987, the Deputy Legal Adviser of the US Department of State, referring to Article 37 of the 1977 Additional Protocol I, affirmed: “We support the principle that individual combatants not kill, injure, or capture enemy personnel by resort to perfidy.” 
United States, Remarks of Michael J. Matheson, Deputy Legal Adviser, US Department of State, The Sixth Annual American Red Cross-Washington College of Law Conference on International Humanitarian Law: A Workshop on Customary International Law and the 1977 Protocols Additional to the 1949 Geneva Conventions, American University Journal of International Law and Policy, Vol. 2, 1987, p. 425.
In 1989, in a memorandum of law, the Office of the Judge Advocate General of the US Department of the Army concluded:
The clandestine, low visibility or overt use of military force against legitimate targets in time of war, or against similar targets in time of peace where such individuals or groups pose an immediate threat to United States citizens or the national security of the United States, as determined by the competent authority, does not constitute assassination or conspiracy to engage in assassination, and would not be prohibited by the proscription in [Executive Order] 12333 or by international law. 
United States, Department of the Army, Office of the Judge Advocate General, Memorandum of Law: Executive Order 12333 and Assassination, 2 November 1989, The Army Lawyer, Pamphlet 27-50-204, December 1989, p. 4.
In 1991, in response to an ICRC memorandum on the applicability of IHL in the Gulf region, the US Department of the Army stated that its practice was consistent with the prohibition of killing, injuring or capturing an adversary by resort to perfidy contained in Article 37 of the 1977 Additional Protocol I. 
United States, Letter from the Department of the Army to the legal adviser of the US Army forces deployed in the Gulf region, 11 January 1991, § 8(J), Report on US Practice, 1997, Chapter 2.8.
The US Air Force Pamphlet (1976) considers that:
Since situations of distress occur during times of armed conflict, as well as peace, and frequently suggest that the persons involved are hors de combat, feigning distress or death, wounds or sickness in order to resume hostilities constitutes perfidy in ground combat. However, a sick or wounded combatant does not commit perfidy by calling for and receiving medical aid even though he may intend immediately to resume fighting … In aerial warfare, it is forbidden to improperly use internationally recognized distress signals to lure the enemy into a false sense of security and then attack. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-6(a); see also § 8-3(a).
The US Naval Handbook (1995) states:
It is a violation of the law of armed conflict to kill, injure or capture the enemy … by feigning shipwreck, sickness, [or] wounds … A surprise attack by a person feigning shipwreck, sickness, or wounds undermines the protected status of those rendered incapable of combat … Such acts of perfidy are punishable war crimes. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.7.
The US Naval Handbook (2007) states:
It is a violation of the law of armed conflict to kill, injure, or capture the enemy … by feigning shipwreck, sickness, [or] wounds … A surprise attack by a person feigning shipwreck, sickness, or wounds undermines the protected status of those rendered incapable of combat. Such acts of perfidy are punishable war crimes. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.7.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, states: “One may commit an act of treachery or perfidy by, for example … feigning incapacitation by wounds or sickness”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.
The US Field Manual (1956) provides: “It is improper to feign surrender so as to secure an advantage over the opposing belligerent thereby.” 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 50.
The manual also stresses: “An individual or a party acts treacherously in displaying a white flag indicative of surrender as a ruse to permit attack upon the forces of the other belligerent.” 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 467.
The manual further states: “In addition to the ‘grave breaches’ of the Geneva Conventions of 1949, the following acts are representative of violations of the law of war (‘war crimes’): … treacherous request for quarter.” 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 504(b).
The US Air Force Pamphlet (1976) considers the feigning of surrender as a perfidious act. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-3(a).
The manual adds:
The use of a … white flag in order to deceive or mislead the enemy, or for any other purpose other than to … surrender, has long been recognized as an act of treachery … [This] expresses the customary and conventional law in this area. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-6(a).
The Pamphlet further provides:
In addition to the grave breaches of the Geneva Conventions of 1949, the following acts are representative of situations involving individual criminal responsibility: … treacherous request for quarter. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 15-3(c)(3).
The US Instructor’s Guide (1985) notes that an
example of a treacherous act would be pretending to surrender in order to facilitate an attack upon an unsuspecting enemy. Such tactics are prohibited because they destroy the basis for the restoration of peace short of the complete destruction of one side or the other. 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 8.
The Guide further provides: “In addition to the grave breaches of the Geneva Conventions, the following acts are further examples of war crimes: … pretending to surrender.” 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 13.
The US Naval Handbook (1995) states: “Feigning surrender in order to lure the enemy into a trap is an act of perfidy.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.1.2.
The Handbook further provides: “It is a violation of the law of armed conflict to kill, injure, or capture the enemy by false indication of an intent to surrender … Such [act] of perfidy [is a] punishable war [crime].” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.7.
In addition, the Handbook states: “The following acts are representative war crimes: … treacherous request for quarter (i.e., feigning surrender in order to gain a military advantage).” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 6.2.5(12).
The US Manual for Military Commissions (2007), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
IMPROPERLY USING A FLAG OF TRUCE.
a. Text. “Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct.”
b. Elements.
(1) The accused used a flag of truce;
(2) The accused made such use of the flag in order to feign an intention to negotiate, surrender, or otherwise suspend hostilities;
(3) The accused had no intention to negotiate, surrender, or otherwise suspend hostilities; and
(4) The conduct took place in the context of and was associated with armed conflict.
c. Maximum punishment. Confinement for 20 years. 
United States, Manual for Military Commissions, published in implementation of the Military Commissions Act of 2006, 10 U.S.C. §§ 948a, et seq., 18 January 2007, Part IV, § 6(18), p. IV-14.
The US Naval Handbook (2007) states: “Feigning surrender in order to lure the enemy into a trap is one example of an act of perfidy.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.1.2.
The Handbook also states: “It is a violation of the law of armed conflict to kill, injure, or capture the enemy by false indication of intent to surrender. … Such acts of perfidy are punishable as war crimes.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.7.
The Handbook further states that “[t]reacherous request[s] for quarter (i.e., feigning surrender in order to gain a military advantage)” are examples of acts that could be considered war crimes. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 6.2.6.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
IMPROPERLY USING A FLAG OF TRUCE.
a. Text. “Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct.”
b. Elements.
(1) The accused used a flag of truce;
(2) The accused made such use of the flag in order to feign an intention to negotiate, surrender, or other wise suspend hostilities;
(3) The accused had no intention to negotiate, surrender, or otherwise suspend hostilities; and
(4) The conduct took place in the context of and was associated with hostilities.
c. Maximum punishment. Confinement for 20 years. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(18), p. IV-15.
The manual also states: “One may commit an act of treachery or perfidy by, for example, feigning an intent to negotiate under a flag of truce or a surrender”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.
The US Military Commissions Act (2006), passed by Congress following the Supreme Court’s decision in Hamdan v. Rumsfeld in 2006, amends Title 10 of the United States Code as follows:
§ 950v. Crimes triable by military commissions
(b) OFFENSES.—The following offenses shall be triable by military commission under this chapter at any time without limitation:
(18) IMPROPERLY USING A FLAG OF TRUCE.—Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2006, Public Law 109-366, Chapter 47A of Title 10 of the United States Code, 17 October 2006, p. 120 Stat. 2629, § 950v(b)(18).
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated:
Perfidious acts include the feigning of an intent to surrender …
[I]ndividual acts of perfidy did occur. On one occasion, Iraqi soldiers waved a white flag and laid down their weapons. When a Saudi Arabian patrol advanced to accept their surrender, it was fired upon by Iraqi forces hidden in buildings on either side of the street. During the same battle, an Iraqi officer approached Coalition forces with his hands in the air, indicating his intention to surrender. When near his would-be-captors, he drew a concealed pistol from his boot, fired, and was killed during the combat that followed. 
United States, Department of Defense, Final Report to Congress on the Conduct of the Persian Gulf War, 10 April 1992, Appendix O, The Role of the Law of War, ILM, Vol. 31, 1992, p. 632.
The US Military Commissions Act (2009) amends Chapter 47A of Title 10 of the United States Code as follows:
§ 950t. Crimes triable by military commission
“The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(18) IMPROPERLY USING A FLAG OF TRUCE.—Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2009, § 950t(18).
The US Field Manual (1956) states: “It is … an abuse of a flag of truce to carry out operations under the protection accorded by the enemy to it and those accompanying it.” 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 467.
The US Air Force Pamphlet (1976) states:
The white flag has traditionally indicated a desire to communicate with the enemy … It raises expectations that the particular struggle is at an end or close to an end since the only proper use of the flag of truce or white flag in international law is to communicate to the enemy a desire to negotiate. Thus, the use of a flag of truce or white flag in order to deceive or mislead the enemy, or for any other purpose other than to negotiate … has long been recognized as an act of treachery … [This] expresses the customary and conventional law in this area. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-6(a)(2); see also § 8-3(a).
The Pamphlet also states: “In addition to the grave breaches of the Geneva Conventions of 1949, the following acts are representative of situations involving individual criminal responsibility: … treacherous request for … truce.” 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 15-3(c)(3).
The US Naval Handbook (1995) provides that it is unlawful to use the flag of truce to gain a military advantage over the enemy. It adds: “Misuse of protective signs, signals and symbols … in order to injure, kill, or capture the enemy constitutes an act of perfidy.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.2.
The US Manual for Military Commissions (2007), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
IMPROPERLY USING A FLAG OF TRUCE.
a. Text . “Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct.”
b. Elements.
(1) The accused used a flag of truce;
(2) The accused made such use of the flag in order to feign an intention to negotiate, surrender, or otherwise suspend hostilities;
(3) The accused had no intention to negotiate, surrender, or otherwise suspend hostilities; and
(4) The conduct took place in the context of and was associated with armed conflict.
c. Maximum punishment. Confinement for 20 years. 
United States, Manual for Military Commissions, published in implementation of the Military Commissions Act of 2006, 10 U.S.C. §§ 948a, et seq., 18 January 2007, Part IV, § 6(18), p. IV-14.
The US Naval Handbook (2007) states that “use of the white flag to gain a military advantage over the enemy is unlawful”. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.2.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, includes in the list of crimes triable by military commissions:
IMPROPERLY USING A FLAG OF TRUCE.
a. Text. “Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct.”
b. Elements.
(1) The accused used a flag of truce;
(2) The accused made such use of the flag in order to feign an intention to negotiate, surrender, or other wise suspend hostilities;
(3) The accused had no intention to negotiate, surrender, or otherwise suspend hostilities; and
(4) The conduct took place in the context of and was associated with hostilities.
c. Maximum punishment. Confinement for 20 years. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(18), p. IV-15.
The manual also states: “One may commit an act of treachery or perfidy by, for example, feigning an intent to negotiate under a flag of truce or a surrender”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.
The US Military Commissions Act (2006), passed by Congress following the Supreme Court’s decision in Hamdan v. Rumsfeld in 2006, amends Title 10 of the United States Code as follows:
§ 950v. Crimes triable by military commissions
“ …
“(b) OFFENSES.—The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(18) IMPROPERLY USING A FLAG OF TRUCE.—Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, surrender, or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2006, Public Law 109-366, Chapter 47A of Title 10 of the United States Code, 17 October 2006, p. 120 Stat. 2629, § 950v(b)(18).
The US Military Commissions Act (2009) amends Chapter 47A of Title 10 of the United States Code as follows:
§ 950t. Crimes triable by military commission
“The following offenses shall be triable by military commission under this chapter at any time without limitation:
“ …
“(18) IMPROPERLY USING A FLAG OF TRUCE.—Any person subject to this chapter who uses a flag of truce to feign an intention to negotiate, … or otherwise suspend hostilities when there is no such intention shall be punished as a military commission under this chapter may direct. 
United States, Military Commissions Act, 2009, § 950t(18).
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated: “Perfidious acts include the feigning of an intent … to negotiate under a flag of truce.” 
United States, Department of Defense, Final Report to Congress on the Conduct of the Persian Gulf War, 10 April 1992, Appendix O, The Role of the Law of War, ILM, Vol. 31, 1992, p. 632.
The US Field Manual (1956) gives the following examples of “improper use of the emblem”:
using a hospital or other building accorded such protection as an observation post or military office or depot; firing from a building or tent displaying the emblem of the Red Cross; using a hospital train or airplane to facilitate the escape of combatants; displaying the emblem on vehicles containing ammunition or other non-medical stores; and in general cloaking acts of hostility. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 55.
The US Air Force Pamphlet (1976) provides:
Medical aircraft cannot retain status as protected medical aircraft during any flight in which they engage in any activity other than the transportation of patients and medical personnel or medical equipment and supplies. Use of the red cross during such a mission would be perfidious and unlawful. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 2-6(e).
The Pamphlet also states that “the feigning by combatants of civilian, non-combatant status” is a perfidious act. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 8-3(a).
The Pamphlet specifies that medical and religious personnel of the armed forces are non-combatants. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 3-4(c).
The US Soldier’s Manual (1984) states: “It is a serious breach of the laws of war when soldiers use these signs [red cross, red crescent and red shield of David] to protect or hide military activities.” 
United States, Your Conduct in Combat under the Law of War, Publication No. FM 27-2, Headquarters Department of the Army, Washington, November 1984, p. 7.
The US Instructor’s Guide (1985) states:
The law of war prohibits treacherous acts. For example, there were occasions in World War II when the Nazis improperly identified buildings as hospitals and certain areas as protected areas. They really used the buildings or areas for direct military purposes such as observation posts, troop billets, defensive positions, or ammunition storage … Such tactics are prohibited because they destroy the basis for the restoration of peace short of the complete destruction of one side or the other. 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 8.
The manual also states:
In addition to the grave breaches of the Geneva Conventions, the following acts are further examples of war crimes: … misusing the Red Cross emblem such as using a medical evacuation helicopter to transport combat troops. 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 13.
The US Naval Handbook (1995) states:
Misuse of protective signs, signals, and symbols … in order to injure, kill, or capture the enemy constitutes an act of perfidy. Such acts are prohibited because they undermine the effectiveness of protective signs, signals, and symbols and thereby jeopardize the safety of noncombatants and the immunity of protected structures and activities. For example, using an ambulance or medical aircraft marked with the red cross or red crescent to carry armed combatants, weapons, or ammunition with which to attack or elude enemy forces is prohibited. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.2.
The US Naval Handbook (2007) states:
Improperly using protective signs, signals, and symbols … to injure, kill, or capture the enemy is an act of perfidy. Such acts are prohibited because they undermine the effectiveness of protective signs, signals, and symbols and thereby jeopardize the safety of noncombatants and the immunity of protected structures and activities. For example, using an ambulance or medical aircraft marked with the red cross or red crescent to carry armed combatants, weapons, or ammunition with which to attack or elude enemy forces is prohibited. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.2.
In the Hagendorf case before the US Intermediate Military Government Court at Dachau in 1946, the accused, a German soldier, was charged with having “wrongfully used the Red Cross emblem in a combat zone by firing a weapon at American soldiers from an enemy ambulance displaying such emblem”. The accused was found guilty. 
United States, Intermediate Military Government Court at Dachau, Hagendorf case, Judgment, 9 August 1946.
In 1992, in its final report to Congress on the conduct of the Gulf War, the US Department of Defense stated: “Perfidious acts include … the feigning of protected status through improper use of the Red Cross or Red Crescent distinctive emblem.” 
United States, Department of Defense, Final Report to Congress on the Conduct of the Persian Gulf War, 10 April 1992, Appendix O, The Role of the Law of War, ILM, Vol. 31, 1992, p. 632.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, states: “One may commit an act of treachery or perfidy by, for example … feigning a protective status by the use of signs, emblems, or uniforms of the United Nations”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.
The US Naval Handbook (1995) states: “Misuse of protective signs, signals and symbols … in order to injure, kill, or capture the enemy constitutes an act of perfidy.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 12.2.
The US Naval Handbook (2007) states: “Improperly using protective signs, signals, and symbols … to injure, kill, or capture the enemy is an act of perfidy.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.2.
According to the US Field Manual (1976), the use of civilian clothing by troops to conceal their military character during battle is an act for which a combatant would lose his right to be treated as a prisoner of war. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 74.
The manual also states: “In addition to the ‘grave breaches’ of the Geneva Conventions of 1949, the following acts are representative of violations of the law of war (‘war crimes’): … use of civilian clothing by troops to conceal their military character during battle.” 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 504(g).
According to the US Air Force Pamphlet (1976), the use of civilian clothing by troops to conceal their military character during battle is an act for which a combatant would lose his right to be treated as a prisoner of war. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 7-2.
The Pamphlet further states: “In addition to the grave breaches of the Geneva Conventions of 1949, the following acts are representative of situations involving individual criminal responsibility: … intentional use of civilian clothing to conceal military identity during battle.” 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 15-3(c)(6).
In respect of air warfare, the Pamphlet states:
Aircrew members do customarily wear uniforms because flight suits fully qualify as uniforms when they are so distinctive in character as to distinguish the wearer from the civilian population … In that connection, the prohibition of perfidy, such as disguising oneself as a civilian in order to engage hostilities, … is applicable. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 7-3(a).
It also provides that, generally speaking, “disguising combatants in civilian clothing in order to commit hostilities constitutes perfidy”. This is also the case of the “feigning by combatants of civilian, noncombatant status”. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, §§ 8-6(a) and 8-3(a).
The US Instructor’s Guide (1985) states: “In addition to the grave breaches of the Geneva Conventions, the following acts are further examples of war crimes: … using civilian clothing to conceal military identity during battle.” 
United States, Instructor’s Guide – The Law of War, Headquarters Department of the Army, Washington, April 1985, p. 13.
The US Naval Handbook (1995) states that illegal combatants may be denied prisoner-of-war status, tried and punished. It also states: “It is a violation of the law of armed conflict to kill, injure, or capture the enemy by false indication of … civilian status … Attacking enemy forces while posing as a civilian puts all civilians at hazard. Such acts of perfidy are punishable as war crimes.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), §§ 12.7. and 12.7.1.
The US Naval Handbook (2007) states:
It is a violation of the law of armed conflict to kill, injure, or capture the enemy by false indication of … civilian status … [A]ttacking enemy forces while posing as a civilian puts all civilians at hazard. Such acts of perfidy are punishable as war crimes. It is also prohibited to kill, injure, or capture an adversary by feigning civilian or noncombatant status. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 12.7.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, states: “One may commit an act of treachery or perfidy by, for example … feigning a civilian, non-combatant status”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.
In 1942, in the Quirin case in which German saboteurs had entered the United States in civilian clothing, the US Supreme Court held:
Each petitioner, in circumstances which gave him the status of an enemy belligerent, passed our military and naval lines, in civilian dress and with hostile purpose. The offense [under the laws of war] was complete when with that purpose they entered – or, having so entered, they remained upon – our territory in time of war without uniform or other appropriate means of identification. 
United States, Supreme Court, Quirin case, Judgment, 31 July 1942, and Extended Opinion, 29 October 1942.
US practice since the Second World War has refused prisoner-of-war treatment to enemy combatants captured in civilian clothing while not carrying their arms openly. During the Vietnam War, the US policy was to consider that all combatants captured during military operations were to be accorded prisoner-of-war status, while terrorists, spies and saboteurs were not. 
George S. Prugh, Law at War: Vietnam 1964-1973, Department of the Army, Vietnam Studies, Washington D.C., 1975, p. 66.
In 1989, in a memorandum of law, the Judge Advocate General of the US Department of the Army stated:
Traditionally, soldiers have an obligation to wear uniforms to distinguish themselves from the civilian population. Law-of-war sources prior to World War II suggested that the prohibition on killing or wounding “treacherously” referred to soldiers disguising themselves as civilians in order to approach an enemy force and carry out a surprise attack. That concept was thrown into disarray during World War II by the reliance on partisans by all parties to that conflict. While frequently characterized as an assassination, the 27 May 1942 ambush of SS General Reinhard Heydrich by British SOE [Special Operations Executive]-trained Czechoslovakian partisans is representative of the practice of each party to the conflict employing organized resistance units to carry out attacks against military units and personnel of an occupying power.
Reliance upon organized partisan forces changed state practice and, accordingly, the law of war. Coordinated British and U.S. revisions of their respective post-World War II law of war manuals reflected this change. For example, the following … italicized … sentence was added to paragraph 31 [of the US Field Manual]:
[Article 23(b) of the 1907 Hague Regulations] is construed as prohibiting assassination … It does not, however, preclude attacks on individual soldiers or officers of the enemy whether in the zone of hostilities, occupied territory, or elsewhere.
The annotations to [the manual] state that the [italicized] sentence was inserted “so as not to foreclose activity by resistance movements, paratroops, and other belligerents who may attack individual persons”. The deliberate decision by many nations to employ surrogate guerrilla forces in lieu of or in connection with conventional military units to fight a succession of guerrilla wars since 1945 has served to raise further doubts regarding the traditional rule.
While state practice suggests that the employment of partisans is lawful, that is, would not constitute assassination, a question remains regarding the donning of civilian clothing by conventional forces personnel for the purpose of killing enemy combatants. However, in the one known case of such practice during World War II, a British officer who successfully entered a German headquarters dressed in civilian attire and killed the commanding general was decorated rather than punished for his efforts. 
United States, Department of the Army, Office of the Judge Advocate General, Memorandum of Law: Executive Order 12333 and Assassination, 2 November 1989, The Army Lawyer, Pamphlet 27-50-204, December 1989, p. 6.
[emphasis in original]
According to the Report on US Practice, the opinio juris of the United States is that:
Customary international law does not … prohibit belligerents from using saboteurs, secret agents or other irregular forces feigning civilian status to attack legitimate military targets. Wear of civilian clothing during an attack, or during a spying or sabotage mission behind enemy lines, may subject combatants to punishment if captured by the enemy. 
Report on US Practice, 1997, Chapter 2.4.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements, states: “One may commit an act of treachery or perfidy by, for example, … feigning a protected status by the use of signs, emblems, or uniforms of … a neutral State or a State not party to the conflict”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 5(17)(c)(4), p. IV-15.