Necessity

A common law defence available as an excuse when an accused acts in response to an urgent and immediate peril that cannot be avoided by obeying the law.

Source

A defence alleging that the tortfeasor’s conduct should be excused on the grounds that he acted in an emergency and the benefit gained by his wrongful act outweighed the harm suffered by the plaintiff.

A justification advanced to counter a claim of state responsibility on the basis that the alleged internationally wrongful act of a state was necessary to protect an essential interest of that state against a grave and imminent peril.