(a) A person commits bigamy when he intentionally contracts or purports to contract a marriage with another person when he has a living spouse. A person who contracts a marriage outside this state, which would be bigamous if contracted in this state, commits bigamy by cohabiting in the state with the other party to such a marriage.
(b) A person does not commit an offense under this section if:
(1) He reasonably believes that his previous marriage is void or was dissolved by death, divorce or annulment; or
(2) He and the prior spouse have been living apart for five consecutive years next prior to the subsequent marriage, during which time the prior spouse was not known by him to be alive.
(3) The burden of injecting the issues under this subsection is on the defendant, but this does not shift the burden of proof.
(c) Bigamy is a Class C felony.