[Sidenote: Annulling illegal marriages.]

Marriages may be annulled for the following causes:

1. Where marriage between the parties is prohibited by law.

2. Where either party was impotent at the time of the marriage.

3. Where either party has a husband or wife at the time of the marriage,
provided they have not continued to live and cohabit together after the
death of the former husband or wife.

4. Where either party was insane or idiotic at the time of the marriage.
[§3422.] If a person marries who has a husband or wife living such
marriage is absolutely void. In case of absence of the husband a
presumption of death does not arise until he has been absent seven years
without intelligence concerning him. Where a party is insane or idiotic,
and is therefore incapable of consenting, a marriage with such person
will be void. When a marriage is absolutely void by law, it is not
necessary to bring an action to annul it, before contracting a
subsequent legal marriage.

[Sidenote: Petition.]

A petition shall be filed in such cases as in actions for divorce, and
all the provisions of this chapter shall apply to such cases except as
otherwise provided. [§3423]

[Sidenote: Validity determined.]