An accused person who puts forward a defence is saying either that she did not commit the offence or, that while she may have committed the offence, there are circumstances which either prevented her from forming an intention to commit the offence or which excuse her from responsibility for the offence. For example, not everyone who kills another person is guilty of murder. A police officer may have to kill in the course of duty in self defence or to defend an innocent bystander.
A person may claim a defence of duress where she commits an offence under threat of death or serious injury. She must believe that the threats will be carried out and must not be part of the original plot to carry out the offence. The threat does not have to be against her. For example, it might be against her child, spouse, or a stranger.
Also, it is not necessary for the person making the threat to be present or in a position to immediately carry out the threats. For instance, if someone tells you to go to another country and commit a crime there and threatens that if you don’t they will harm your family and then you commit the crime, then this defence may be available to you. However, the crime committed needs to be at most proportional to the threat made. In other words the threat(s) must be very serious in nature. In order for the defence to be valid, there must also be no other safe avenue of escape for the person committing the offence. In other words, an accused person cannot rely on the defence of duress if he or she has an opportunity to get out of the situation of duress safely. The accused must raise the defence and provide sufficient evidence to show that it was demonstrably impossible to comply with the law.
Finally, this defence is not available for all offences. Excluded offences include murder, attempted murder, robbery, arson, forcible abduction, and sexual assault.
Mistake of Fact
This defence arises from the requirement that the Crown must prove beyond a reasonable doubt that the accused not only committed the guilty act, but also had the necessary guilty mind. Mistake of fact may be used as a defence where the mistake is such that it misleads the accused into thinking that she is either not committing an offence at all or is committing a less serious offence than the one she actually commits. For example, Bill tells Ann that Charlie has taken his bicycle, and asks her to get it back. Ann has seen Bill riding the bicycle in the past and believes that Bill owns the bike. Ann takes the bike from Charlie and returns it to Bill. If the bike in fact belongs to Charlie, Ann may have the defence of mistake of fact.
Mistake of Law
Ignorance of the law is no excuse. We cannot avoid responsibility for committing a wrongful act by claiming that we did not know that it was an offence, despite the fact that it is impossible to be aware of every law and regulation. However, there have been cases where the courts have decided that it would be unfair to convict the accused where she was not properly informed of the offence. The Courts rely on the specific facts of each case when deciding whether mistake of law is a valid defence.
Not Criminally Responsible on Account of Mental Disorder
The issue of an accused being not criminally responsible on account of mental disorder may be raised by the accused or by the prosecution. The Court must be convinced that, at the time of the offence, the accused was unable to understand the “nature and quality” of her actions, or that she did not know that what she was doing was wrong due to her mental disorder.
A hearing is conducted by a Review Board to decide whether the accused is fit to stand trial. The Judge may send her for observation for up to thirty days (sixty in some circumstances). If she is found unfit to stand trial, or if she is acquitted at trial due to her mental disorder, the Judge will order her kept in custody until the Lieutenant Governor makes an order directing where she will be kept, or whether she will be released. She may be released with or without conditions. When considering whether to release the accused, the Lieutenant Governor must consider the best interests of the accused and the public.
A person who is attacked by another has the right to defend herself. She must use no more force than is necessary to repel the attack. She may be justified in killing her attacker or causing him serious bodily harm if she has reasonable grounds to believe that it is the only way to save herself from death or serious injury.
The belief of the accused that she was in danger must have been reasonable at the time of the offence. In coming to that conclusion, the court may consider evidence of the attacker’s violent nature. A person who assaults another and is then attacked by that person may be justified in using force to repel the attack. She must not have committed the original assault with the intention of causing death or serious injury. She may only use as much force as is necessary to repel the attack and must be able to show that she tried to avoid further conflict and to retreat from the attack. For example, Ann pushes Bill. In response Bill punches and kicks Ann. Ann tries to run away but is stopped by Bill. Ann may be justified in using force to repel Bill’s attack. A person may also use no more force than necessary to prevent someone from taking her property, or to prevent someone from breaking into her home. However, it is never permissible to kill or cause serious bodily injury in preventing these kinds of things unless it is a measure of self-defence.
Pre-Menstrual Syndrome (PMS)
PMS is not a defence but has been accepted as a mitigating factor when considering sentence. If there is some clear medical evidence that the woman suffers from PMS and did so at the time of the offence, it may serve to reduce her sentence.
Drunkenness has been accepted as a defence for committing an offence, but this defence will only succeed under certain circumstances. If a person is so intoxicated that she is incapable of forming the necessary specific intention to commit the crime, then the person cannot be found guilty. However, a person may still be found guilty of a lesser offence requiring a less specified degree of intention. In the case of murder, drunkenness may reduce the offence from murder to manslaughter.
Provocation does not justify, and is not a defence to, an assault although it may lessen the sentence. Provocation includes blows, words, or gestures. Provocation is a limited defence to a charge of murder. In other words, if an accused can show that she was provoked prior to committing murder and that she acted in the heat of passion, the charge may be reduced to manslaughter. The provocation must have been enough to cause an ordinary person to lose self-control.
Battered Woman’s Defence
Depending on the history of the relationship between a woman and her partner, she may be able to raise the battered woman’s defence. This defence applies if there has been repeated violence in the relationship and, at the time of the offence, the accused woman feared for her life or felt that she would suffer serious bodily harm. This is different from regular self-defence where the accused woman must show that she was in immediate danger at the time of the offence.
However, the accused woman must still show that her belief that she was in danger was reasonable at the time, and she must have used reasonable force in defending herself.