Revised Statutes of Missouri — Title X (Taxation and Revenue)
§ 143.491 RSMo — Returns by husband and wife
1. A combined return shall be filed by a husband and wife who file a joint federal return even though one of them has neither income nor deductions. The tax liability of the two taxpayers shall be separate and not joint and several.
2. Separate returns shall be filed by a husband and wife who do not file a joint federal return.
Source: official text