Related Rule
Argentina
Practice Relating to Rule 65. Perfidy
Argentina’s Law of War Manual (1969) provides that “the use of ruses and stratagems of war shall be legitimate as long as they do not imply the recourse to treason or to perfidy”, which are violations of the principle of good faith. 
Argentina, Leyes de Guerra, RC-46-1, Público, II Edición 1969, Ejército Argentino, Edición original aprobado por el Comandante en Jefe del Ejército, 9 May 1967, § 1.017.
Argentina’s Law of War Manual (1989) states:
Those acts are perfidious, which, relying on the good faith of an adversary with the intention to betray him, lead him to believe that he is entitled to, or is obliged to accord, protection under the rules of international law …
The prohibition of employing perfidious methods does not include stratagems. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2) and (3).
Argentina’s Law of War Manual (1989) provides: “It is prohibited to employ perfidious methods to kill, injure or capture an adversary.” 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(1).
Argentina’s Law of War Manual (1989) states that “feigning incapacitation by wounds or sickness” is an example of perfidy. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(2).
Argentina’s Law of War Manual (1989) provides that “feigning the intent … to surrender” is an example of perfidy. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(1).
It also states that “the perfidious use … of … recognized protective signs” is a grave breach of the 1977 Additional Protocol I and a war crime. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 8.03.
At the Battle of Goose Green during the War in the South Atlantic, Argentine soldiers raised a white flag. As UK soldiers moved forward to accept the surrender, they were fired on and killed from a neighbouring position, probably in the confusion. 
Max Hastings and Simon Jenkins, The Battle of the Falklands, W. W. Norton & Company, London, 1983, p. 247; Geoffrey Best, War and Law Since 1945, Clarendon Press, Oxford, 1997, p. 292; Christopher Greenwood, Scope of Application of Humanitarian Law, in Dieter Fleck (ed.), The Handbook of Humanitarian Law in Armed Conflicts, Oxford University Press, Oxford, 1995, § 223; Martin Middlebrook, Task Force: The Falklands War, 1982, Penguin Books, 1988, pp. 269-270.
Argentina’s Law of War Manual (1969) provides especially for the prohibition of the improper use of the flag of truce, which is considered a breach of good faith. It states, however, that the use said to be “improper” applies only in combat operations. 
Argentina, Leyes de Guerra, RC-46-1, Público, II Edición 1969, Ejército Argentino, Edición original aprobado por el Comandante en Jefe del Ejército, 9 May 1967, § 1.017.
Argentina’s Law of War Manual (1989) gives “simulating the intent to negotiate under a flag of parlementaires” as an example of perfidy. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(1).
The manual also states that “the perfidious use … of … recognized protective signs” is a grave breach of the 1977 Additional Protocol I and a war crime. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 8.03.
Under Argentina’s Law of War Manual (1989), “the perfidious use of the sign of the Red Cross or Red Crescent” constitutes a grave breach of the 1977 Additional Protocol I and a war crime. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 8.03.
Argentina’s Law of War Manual (1989) provides that it is an example of perfidy “to make use of the signs, emblems or uniforms of the United Nations … so as to simulate a protected status”. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(4).
The manual adds that “the perfidious use of … recognized protective signs” is a grave breach of the 1977 Additional Protocol I and a war crime. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 8.03.
Argentina’s Law of War Manual (1989) provides that “the perfidious use of … recognized protective signs” is a grave breach of the 1977 Additional Protocol I and a war crime. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 8.03.
Argentina’s Law of War Manual (1989) states that “feigning the condition of a civilian non-combatant person” is an example of perfidy. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(3).
Argentina’s Law of War Manual (1989) states that “making use of signs, emblems or uniforms … of neutral states or other states which are not parties to the conflict, so as to simulate a protected status” is an example of perfidy. 
Argentina, Leyes de Guerra, PC-08-01, Público, Edición 1989, Estado Mayor Conjunto de las Fuerzas Armadas, aprobado por Resolución No. 489/89 del Ministerio de Defensa, 23 April 1990, § 1.05(2)(4).