11 Del. C. § 1002: Bigamy; defenses.

In any prosecution for bigamy it is a defense that, at the time of the allegedly bigamous marriage:

(1) The accused believed, after diligent inquiry, that the prior spouse was dead; or

(2) The parties to the former marriage had been living apart for 7 consecutive years throughout which the accused had no reasonable grounds to believe that the prior spouse was alive; or

(3) A court in any American or foreign jurisdiction had entered a judgment purporting to terminate or annul any prior disqualifying marriage, and the accused did not know that judgment to be invalid; or

(4) The accused otherwise reasonably believed that the accused was legally eligible to remarry.