Factual Innocence:If the Crown is unable to prove the essential elements of the particular offence beyond a reasonable doubt, they will have failed to discharge their burden, and the accused will be acquitted.
Self-Defence: One's actions may be justified in certain circumstances, such as where one has to protect himself or someone else. In order to successfully argue self-defence, one must be able to demonstrate that:
there were reasonable grounds believe that he or others were at risk of acts of force or the threat of force;
the accused's actions were committed for the purpose of defending or protecting themselves or someone else; and
the act committed was reasonable in the circumstances.
Non-Mental Disorder Automatism: Automatism can be raised as a defence in rare circumstances. Automatism deals with unconscious and involuntary behaviour. Examples of causes of non-mental disorder automatism include: sleep disorders, a blow to the head, or the involuntarily consumption of an illegal substance.
Mental Disorder Automatism: If someone is found not criminally responsible as a result of mental disorder, they are still guilty of the act, but will have lacked the mental intention required.
Provocation: There is also a partial defence of Provocation. When an intentional killing occurred in circumstances where the Accused was provoked or severely intoxicated, a defence of Provocation or Intoxication may be argued. Given the current state of the law, however, Murder cases are not often reduced to Manslaughter as a result of Provocation or Intoxication.