Define bigamy, its essentials, statutory exceptions and defence.

Marriage — the family-law institution (Family Law, Semester 4's civil side) — is also a criminal law's protected status: the state polices who may marry, how many may be married, and on what truth the marriage rests. The Code's marriage-offence chapter punishes marriages that violate the statutory conditions (the marriage age — twenty years for both parties in Nepal, the world's highest uniform bar, the national policy choice); the monogamy condition; the prohibited-degrees (consanguinity) condition; and the consent-through-fraud condition. The design logic: the marriage's validity (civil) and the marriage's criminality (penal) — two tracks, one institution (a void marriage's parties may also be criminals; but the crime and the nullity are distinct questions — the exam's recurring distinction).