Mississippi Code
In General
§ 13-1-5. Competency of husband and wife

Husbands and wives may be introduced by each other as witnesses in all cases, civil or criminal, and shall be competent witnesses in their own behalf, as against each other, in all controversies between them. Either spouse is a competent witness and may be compelled to testify against the other in any criminal prosecution of either husband or wife for a criminal act against any child, for contributing to the neglect or delinquency of a child, or desertion or nonsupport of children under the age of sixteen (16) years, or abandonment of children. But in all other instances where either of them is a party litigant the other shall not be competent as a witness and shall not be required to answer interrogatories or to make discovery of any matters involved in any such other instances without the consent of both.