The Criminal Code outlines circumstances when a person in authority can reasonably use lethal force against another person in section 27.
Use of force to prevent commission of offence
27 Every one is justified in using as much force as is reasonably necessary
(a) to prevent the commission of an offence
(i) for which, if it were committed, the person who committed it might be arrested without warrant, and
(ii) that would be likely to cause immediate and serious injury to the person or property of anyone; or
(b) to prevent anything being done that, on reasonable grounds, he believes would, if it were done, be an offence mentioned in paragraph (a).
Protection of persons acting under authority
25 (1) Every one who is required or authorized by law to do anything in the administration or enforcement of the law
(a) as a private person,
(b) as a peace officer or public officer,
(c) in aid of a peace officer or public officer, or
(d) by virtue of his office,
is, if he acts on reasonable grounds, justified in doing what he is required or authorized to do and in using as much force as is necessary for that purpose.
(2) Where a person is required or authorized by law to execute a process or to carry out a sentence, that person or any person who assists him is, if that person acts in good faith, justified in executing the process or in carrying out the sentence notwithstanding that the process or sentence is defective or that it was issued or imposed without jurisdiction or in excess of jurisdiction.
Marginal note:When not protected
(3) Subject to subsections (4) and (5), a person is not justified for the purposes of subsection (1) in using force that is intended or is likely to cause death or grievous bodily harm unless the person believes on reasonable grounds that it is necessary for the self-preservation of the person or the preservation of any one under that person’s protection from death or grievous bodily harm.
Marginal note:When protected
(4) A peace officer, and every person lawfully assisting the peace officer, is justified in using force that is intended or is likely to cause death or grievous bodily harm to a person to be arrested, if
(a) the peace officer is proceeding lawfully to arrest, with or without warrant, the person to be arrested;
(b) the offence for which the person is to be arrested is one for which that person may be arrested without warrant;
(c) the person to be arrested takes flight to avoid arrest;
(d) the peace officer or other person using the force believes on reasonable grounds that the force is necessary for the purpose of protecting the peace officer, the person lawfully assisting the peace officer or any other person from imminent or future death or grievous bodily harm; and
(e) the flight cannot be prevented by reasonable means in a less violent manner.
Marginal note:Power in case of escape from penitentiary
(5) A peace officer is justified in using force that is intended or is likely to cause death or grievous bodily harm against an inmate who is escaping from a penitentiary within the meaning of subsection 2(1) of the Corrections and Conditional Release Act, if
(a) the peace officer believes on reasonable grounds that any of the inmates of the penitentiary poses a threat of death or grievous bodily harm to the peace officer or any other person; and
(b) the escape cannot be prevented by reasonable means in a less violent manner.