Related Rule
Canada
Practice Relating to Rule 57. Ruses of War
Canada’s Rules of Engagement for Operation Deliverance (1992) provides:
Commanders are authorized to use military deception to protect against attack and to enhance the security and effectiveness of Canadian forces. Commanders may employ any deception means available to deny potentially hostile forces the ability to accurately locate, identify, track, and target Canadian or Coalition forces except as constrained or otherwise prohibited by international law or agreement, directive or these ROE. 
Canada, Canadian Joint Force Somalia: Rules of Engagement Operation Deliverance, completed on 11 December 1992, reprinted in James M. Simpson, Law Applicable to Canadian Forces in Somalia 1992/93. A study prepared for the Commission of Inquiry into the Deployment of Canadian Forces to Somalia, Minister of Public Works and Government Services, Ottawa, 1997, Appendix, pp. 73–80, § 27.
Canada’s LOAC Manual (1999) states:
Ruses of war are measures taken to obtain advantage of the enemy by confusing or misleading them.
Ruses of war are more formally defined as acts which are intended to mislead an adversary or to induce that adversary to act recklessly. Ruses must not infringe any rule of the LOAC. Ruses are lawful if they are not treacherous, perfidious and do not violate any express or tacit agreement.
The following are examples of ruses which are lawful:
a. surprises;
b. ambushes;
c. feigning attacks, retreats or flights;
d. simulating quiet and inactivity;
e. giving large strong points to a small force;
f. constructing works, bridges etc. which it is not intended to use;
g. transmitting bogus signal messages and sending bogus dispatches and newspapers with a view to their being intercepted by the enemy;
h. making use of the enemy’s signals, watchwords, wireless code signs, tuning calls and words of command;
i. conducting a false military exercise on the wireless on a frequency easily intercepted while substantial troop movements are taking place elsewhere;
j. pretending to communicate with troops or reinforcements that do not exist;
k. moving landmarks;
l. constructing dummy airfields and aircraft;
m. putting up dummy guns or dummy tanks;
n. laying dummy mines;
o. removing badges from uniforms;
p. clothing the men of a single unit in the uniforms of several different units to induce the enemy to believe that they face a large force; or
q. giving false ground signals to enable airborne personnel or supplies to be dropped in a hostile area or to induce aircraft to land in a hostile area. 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, pp. 6-1 and 6-2, §§ 5–7 (land warfare); see also p. 7-2, §§ 14 and 15 (air warfare) and p. 8-10, §§ 75–77 (naval warfare).
In the context of air warfare, the manual also gives camouflage, decoys and fake radio signals as examples of legitimate ruses. 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 7-2, § 15.
Canada’s Code of Conduct (2001) states: “Ruses such as camouflage and other similar deceptions are not prohibited and as such are legitimate.” 
Canada, Code of Conduct for CF Personnel, Office of the Judge Advocate General, 4 June 2001, Rule 10, § 10.
Canada’s LOAC Manual (2001) states in its chapter on land warfare:
1. Ruses of war are measures taken to obtain advantage of the enemy by confusing or misleading them.
2. Ruses of war are more formally defined as acts, which are intended to mislead an adversary or to induce that adversary to act recklessly. Ruses must not infringe any rule of the LOAC. Ruses are lawful if they are not treacherous, perfidious and do not violate any express or tacit agreement.
3. The following are examples of ruses, which are lawful:
a. surprises;
b. ambushes;
c. feigning attacks, retreats or flights;
d. simulating quiet and inactivity;
e. giving large strong points to a small force;
f. constructing works, bridges, etc., which it is not intending to use;
g. transmitting bogus signal messages, and sending bogus dispatches and newspapers with a view to their being intercepted by the enemy;
h. making use of the enemy’s signals, watchwords, wireless code signs, tuning calls and words of command;
i. conducting a false military exercise on the wireless on a frequency easily intercepted while substantial troop movements are taking place elsewhere;
j. pretending to communicate with troops or reinforcements that do not exist;
k. moving landmarks;
l. constructing dummy airfields and aircraft;
m. putting up dummy guns or dummy tanks;
n. laying dummy mines;
o. removing badges from uniforms;
p. clothing the men of a single unit in the uniforms of several different units to induce the enemy to believe that they face a large force; or
q. giving false ground signals to enable airborne personnel or supplies to be dropped in a hostile area, or to induce aircraft to land in a hostile area. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 602.
In its chapter on air warfare, the manual states:
1. Ruses of war are measures taken to obtain advantage of the enemy by confusing or misleading them.
2. Ruses of war are more formally defined as acts that are intended to mislead an adversary or to induce that adversary to act recklessly. Ruses must not infringe any rule of the LOAC. Ruses are lawful if they are not treacherous, perfidious and do not violate any express or tacit agreement. Examples of legitimate ruses include camouflage, decoys and fake radio signals. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 705.
In its chapter on naval warfare, the manual states:
1. Ruses of war are measures taken to obtain advantage of the enemy by confusing or misleading them.
2. Ruses of war are more formally defined as acts, which are intended to mislead an adversary or to induce that adversary to act recklessly. Ruses must not infringe any rule of the LOAC. Ruses are lawful if they are not treacherous, perfidious and do not violate any express or tacit agreement.
3. The following are examples of ruses, which are lawful:
a. surprises;
b. feigning attacks, retreats or flights;
c. simulating quiet and inactivity;
d. transmitting bogus signal messages, and sending bogus dispatches and newspapers with a view to their being intercepted by the enemy;
e. making use of the enemy’s signals, watchwords, wireless code signs, tuning calls and words of command;
f. conducting a false military exercise on the wireless on a frequency easily intercepted while substantial naval operations are taking place elsewhere; and
g. pretending to communicate with forces that do not exist. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 856.1–3.
Canada’s Code of Conduct (2005) states:
False and improper use of the Red Cross/Red Crescent emblem is prohibited. The use of the Red Cross to shield the movement of troops or ammunitions is also prohibited. Perfidy is a war crime. Committing a hostile act under the cover of the protection provided by the distinctive emblem would constitute perfidy. Ruses such as camouflage and other similar deceptions are not prohibited and as such are legitimate. 
Canada, Code of Conduct for CF Personnel, Office of the Judge Advocate General, 2005, Rule 10, § 10.