Because every case is different, the best defence to an assault charge will depend heavily on the particular circumstances of the offence. However, the following are some potential defences to the charge of assault:
Consent may be a defence when defending assault charges. The burden is on the Crown Prosecutor to prove beyond a reasonable doubt that the person who was allegedly assaulted did not consent to the application of force by the accused person. However, an important limit to this defence is the fact that there is no such thing as consent to bodily harm. Because in law we do not find it permissible to consent to bodily harm, the defence of consent will not operate in any circumstance where there has been an intentional application of force that caused serious bodily harm. For example, you cannot consent to being stabbed or consent to suffering potentially damaging physical harm in the context of a fist fight. This being said, you cannot use consent as a defence if you have been charged with assault causing bodily harm, or aggravated assault.
You are justified in using reasonable force–i.e., as much as is “reasonably necessary” in the circumstances–to defend yourself against an unlawful assault, provided you did not intend to cause death or grievous bodily harm. For this reason, self-defence may also be a defence to an assault charge. However, in order to successfully argue that you acted for the purposes of self-defence, you will need to prove that you had reasonable grounds to believe that force was being used against you or another person, and that you acted reasonably in the circumstances. The reasonableness of your actions will be determined by a number of factors including, but not limited to:
- The nature of the force or threat used against you;
- Your role in the incident;
- Whether anyone was using or threatening to use a weapon;
- The size, age, gender and physical capabilities of the people involved in the incident;
- The relationship between you and those involved in the incident; and,
- Whether the force you used was proportional to the force used by your aggressor. Generally speaking, this defence will not succeed if the force you used was far greater than that used against you. For example, you cannot shoot someone who’s trying to punch you.
If the assault was an accident, you should not be found guilty of a criminal offence as you would lack the mental intent necessary to be guilty of assault. However, in order to raise the defence of accident after you have been charged with assault, you will need to prove that the accident or event was unforeseeable. In law an accident has to be something that happened unexpectedly, outside of the usual course of things, and any harm or loss flowing from the accident had to be unintended and unexpected.
As such, you will not be able to argue this defence if you took an action that had foreseeable consequences, but then tried to pass it off as an ‘accident’. For example, it would not be an accident if you pretended that you were going to punch someone, but accidentally actually ended up hitting them. It is foreseeable that striking the area around another person could result in you actually striking that person, and therefore, the consequence of your actions was not totally unforeseeable.
If you want to raise the defence of accident, you will have the burden of demonstrating that there is an air of reality to the notion that your actions were accidental. If you are successful in doing so, the Crown Prosecutor will only be able to convict you if they can then prove beyond a reasonable doubt that your actions were not accidental.