How to Determine the Crime of Bigamy
 Bigamy refers to the illegal act of a person who has a spouse and marries another person, that is, one person has two or more marriage relationships at the same time.
 Article 258 of the Criminal Law stipulates: "Whoever has a spouse and bigamy, or knowingly marries another person with a spouse, shall be sentenced to fixed-term imprisonment of not more than two years or criminal detention."
 There are two types of people who constitute bigamy. The first type is a person who has a spouse and is registered to marry another person, or lives together with another person in the name of husband and wife. The second type is a person who knows that another person has a spouse and is registered to marry another person, or lives together in the name of husband and wife. Among them, the second category of people who constitute bigamy requires "knowing that another person has a spouse". If they know in advance or know afterwards and continue to maintain the marriage relationship, they are "knowing". On the contrary, ignorance and deception do not constitute bigamy.
 The determination of bigamy depends on whether it constitutes another marital relationship. According to the relevant judicial interpretation, there are two cases of bigamy: one is legal bigamy, which means that a person with a spouse registers marriage with others; the other is de facto bigamy, which means that a person with a spouse lives with others in the name of husband and wife. Under any of the following circumstances, it shall be deemed that they live together in the name of husband and wife:
 (1) Having a spouse holding a marriage ceremony with another person
 (2) A person with a spouse, though not holding a marriage ceremony with another person, is called a husband and wife or considers himself or herself as a husband and wife.
 The husband and wife are commensurate. In addition to the recognition between the parties and the address between the parties in their daily life, the parties live together. When the woman is sick, the man signs in the name of the husband and accompanies her. When the woman gives birth to children, the man signs in the name of the father in the hospital. The parties celebrate the full moon for their children in the name of their parents. These can also be used as supporting evidence to determine the proportionality between husband and wife. To identify bigamy, it is usually necessary to obtain testimonies from the surrounding people and their relatives and friends to prove that the surrounding people think the parties are husband and wife.