The amount of force necessary to protect oneself or one's property. Reasonable force is a term associated with defending one's person or property from a violent attack, theft, or other type of unlawful aggression. It may be used as a defense in a criminal trial or to defend oneself in a suit alleging tortious conduct. If one uses excessive force, or more than the force necessary for such protection, he or she may be considered to have forfeited the right to defense. Reasonable force is also known as legal force.
A person is generally justified in using force that is intended or likely to cause death or great bodily harm if the person reasonably believes that such force is necessary to prevent the commission of a forcible felony. The person is also generally justified in using such extreme force to prevent or terminate another's unlawful entry into or attack upon a dwelling, if: (1) the entry is made or attempted in a violent manner and he reasonably believes that such force is necessary to prevent personal violence to himself or another then in the dwelling, or (2) he reasonably believes that such force is necessary to prevent the commission of a felony in the dwelling.