Legal Definitions - trigamy

Definition: Trigamy (trig-uh-mee) is the act of marrying a person while legally married to someone else and bigamously married to yet another.

For example, if a person named D marries A, and then marries B while still married to A, and later marries C after A has died but B is still alive, the marriage to C is not considered bigamy because the marriage to B was bigamous and void.

Trigamy is a special situation that arises when the validity of the alleged prior marriage is a good defense to a charge of bigamy. In other words, if a person can prove that the alleged prior marriage relied upon to support the charge of bigamy was itself void because of an even earlier marriage existing at the time, then the charge of bigamy may be defeated.