Therefore, the evidence that bigamy needs to be investigated by public security organs can be divided into two situations:
1. Legal marriage with marriage certificate. In this case, obtaining evidence is relatively simple. The evidence needed is marriage registration. 2, cohabiting in the name of husband and wife did not get a marriage certificate. Because there is no direct evidence like the previous bigamy, it will be more troublesome to obtain evidence. Specific evidence that can be collected: forged marriage documents, birth certificates of children born with a third party, witness testimony of friends, letter of guarantee from the party suspected of bigamy, photos and videos of men and women going out together, intimate information sent by both parties, etc.
Legal basis:
Criminal law of the people's Republic of China
Article 258 Whoever commits bigamy while having a spouse, or marries while knowing that others have a spouse, shall be sentenced to fixed-term imprisonment of not more than two years or criminal detention.