This is a common law offence which means that it does not come under particular legislation. The law surrounding it is from case law rather than legislation by parliament.

If you look at what must be proved that is basically what the law is in relation to this charge.

There is then a lot of case law that explains this law in greater detail.

As a common law offence there is no maximum penalty. It can be punished by fine or imprisonment or both.

There is no limit to the penalty unless it is inordinate(excessive).

(a) The accused unlawfully assaulted or beat another person.

(a) Duress.

(b) Factual dispute.

(c) Identification dispute.

(d) Lack of intent.

(e) Mental impairment.

(f) Necessity.

(g) Self-defence.