Family Code, Art. 41

A marriage contracted by any person during subsistence of a previous marriage shall be null and void, unless before the celebration of the subsequent marriage, the prior spouse had been absent for four consecutive years and the spouse present has a well-founded belief that the absent spouse was already dead. In case of disappearance where there is danger of death under the circumstances set forth in the provisions of Article 391 of the Civil Code, an absence of only two years shall be sufficient. For the purpose of contracting the subsequent marriage under the preceding paragraph the spouse present must institute a summary proceeding as provided in this Code for the declaration of presumptive death of the absentee, without prejudice to the effect of reappearance of the absent spouse. (83a)