Answer
Under Article 55 of the Family Code, a petition for legal separation may be filed on any of these grounds: (1) repeated physical violence or grossly abusive conduct against the petitioner, a common child, or a child of the petitioner; (2) physical violence or moral pressure to compel a change of religious or political affiliation; (3) an attempt to corrupt or induce the petitioner or a child to engage in prostitution; (4) a final judgment sentencing the respondent to more than six years of imprisonment; (5) drug addiction or habitual alcoholism; (6) lesbianism or homosexuality; (7) contracting a subsequent bigamous marriage; (8) sexual infidelity or perversion; (9) an attempt against the life of the petitioner; or (10) abandonment of the petitioner without justifiable cause for more than one year.
Legal separation does not dissolve the marriage — it allows the spouses to live apart and separates their property. The petition must be filed within five years from the occurrence of the cause (Article 57), and the court cannot try the case until at least six months have elapsed from its filing (the cooling-off period, Article 58).