PART II - GENERAL PRINCIPLES OF CRIMINAL LIABILITY
Self defence
20. (1) No person shall be criminally responsible for the use of force in repelling an unlawful attack -
(a) upon himself or herself or another person if -
(i) it was not reasonable to avail himself or herself of any means of retreat of which he or she was aware; and
(ii) the degree of force used in repelling the attack was no greater than that which was reasonably necessary in the circumstances;
(b) upon his or her property or the property of another provided that the means he or she chooses and the degree of force he or she uses in so doing are reasonable in the circumstances.
Self-defence - national proceedings
EDIT.