CALIFORNIA FAMILY LAW
...Marital Status
......Nullity
.........Estoppel
2 Cards On This Topic:

“The validity of a divorce decree cannot be contested by a party who has procured the decree or a party who has remarried in reliance thereon, or by one who has aided another to procure the decree so that the latter will be free to remarry.”

Quasi-estoppel does not apply to a party who had no role in procuring, or knowledge of facts regarding, other spouse's previous divorce.