Duress

In jurisprudence, duress or coercion refers to a situation whereby a person performs an act as a result of violence, threat or other pressure against the person. Black's Law Dictionary (6th ed.) defines duress as "any unlawful threat or coercion used... to induce another to act [or not act] in a manner [they] otherwise would not [or would]". Duress is pressure exerted upon a person to coerce that person to perform an act that he or she ordinarily would not perform. The notion of duress must be distinguished both from undue influence in the civil law. In criminal law, duress and necessity are different defenses.

Duress has two aspects. One is that it negates the person's consent to an act, such as sexual activity or the entering into a contract; or, secondly, as a possible legal defense or justification to an otherwise unlawful act. A defendant utilizing the duress defense admits to breaking the law, but claims that he/she is not liable because, even though the act broke the law, it was only performed because of extreme unlawful pressure. In criminal law, a duress defense is similar to a plea of guilty, admitting partial culpability, so that if the defense is not accepted then the criminal act is admitted.

Duress or coercion can also be raised in an allegation of rape or other sexual assault to negate a defense of consent on the part of the person making the allegation.

A defendant who raises a defense of duress has actually done everything to constitute the actus reus of the crime and has the mens rea because he or she intended to do it in order to avoid some threatened or actual harm. Thus, some degree of culpability already attaches to the defendant for what was done.

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