Norma relacionada
Canada
Practice Relating to Rule 101. The Principle of Legality
Canada’s LOAC Manual (1999) provides that no prisoner of war “may be tried or punished for any offence which was not, at the time of its commission, forbidden by International Law or the law of the Detaining Power”. 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 10-7, § 76.
With respect to occupied territories, the manual states: “The penal provisions enacted by the occupant must not be retroactive.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 12-6, § 49(a).
The manual further provides: “No person may be tried for a war crime unless the crime in question was an offence at the time of its commission in accordance with national legislation or International Law.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 16-6, § 42.
The same provision applies to non-international armed conflicts. 
Canada, The Law of Armed Conflict at the Operational and Tactical Level, Office of the Judge Advocate General, 1999, p. 17-3, § 29(c).
Canada’s LOAC Manual (2001) states in its chapter on the treatment of prisoners of war (PWs): “No PW may be tried or punished for any offence, which was not, at the time of its commission, forbidden by International Law or the law of the Detaining Power.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 1040.2.
In its chapter on rights and duties of occupying powers, the manual states: “Under [the 1949 Geneva Convention IV] the legislative powers of the occupant in the sphere of criminal law are restricted in the following ways: a. The penal provisions enacted by the occupant must not be retroactive”. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 1229.1.a.
In its chapter on “War crimes, individual criminal liability and command responsibility”, the manual further states: “No person may be tried for a war crime unless the crime in question was an offence at the time of its commission in accordance with national legislation or International Law.” 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 1617.5.
In its chapter on non-international armed conflicts, the manual states:
As a minimum, accused persons:
c. shall not be found guilty of an offence in respect of any act or omission which was not an offence at the time of commission, nor shall any punishment be more severe than was applicable at that time, although, if the punishment has been alleviated, the accused shall benefit accordingly. 
Canada, The Law of Armed Conflict at the Operational and Tactical Levels, Office of the Judge Advocate General, 13 August 2001, § 1716.2.c.
In 2013, in the Sapkota case, Canada’s Federal Court dismissed a request for review of a decision denying refugee protection to the applicant on grounds of complicity in crimes against humanity in Nepal between 1991 and 2009. While reviewing the submissions of the respondent, Canada’s Minister of Citizenship and Immigration, the Court stated: “The Respondent notes that the Rome Statute of the International Criminal Court … is endorsed in Canada as a source of customary law.” 
Canada, Federal Court, Sapkota case, Reasons for Judgment and Judgment, 15 July 2013, § 28.