threat, in law, declaration of intent to injure another by doing an unlawful act, with a view to restraining his freedom of action. A threat is distinguishable from an assault, for an assault requires some physical act that appears likely to eventuate in violence, whereas a threat may consist of words only or an act that is not violent, e.g., unlawful prosecution. Threats made to obtain money or property wrongfully are crimes (see blackmail and extortion), and under some statutes, the mere sending of nonextortionate letters that announce an intent to injure the person or property of another is criminal. Any contract concluded while one party is deprived of his freedom of will by a threat (see duress) is invalid and may be set aside.