Yes, it is illegal to marry your first cousin in Louisiana under state law. Louisiana Civil Code Article 90 prohibits marriages between collaterals within the fourth degree of kinship, which includes first cousins.
Louisiana’s Marriage Prohibitions
Degrees of Consanguinity
First cousins share grandparents, placing them in the fourth degree of collateral relationship by civil law reckoning. This ban applies to both full and half-blood relations, as well as adoptive ties.
Second cousins and more distant kin fall outside this limit and may marry freely. The rule aims to prevent close genetic unions while allowing broader family ties.
No Exceptions for Blood Relatives
Unlike adoptive collaterals—who can seek court approval—biological first cousins have no waiver path. Marriages attempted in Louisiana are null from inception, lacking legal force for inheritance or spousal rights.
Out-of-state cousin marriages receive mixed recognition; courts have upheld some but stress public policy against incestuous unions.
Historical Context
Louisiana codified the cousin ban in 1902, building on French civil law traditions. Earlier eras permitted such unions, but modern statutes prioritize genetic health concerns.
Incest statutes (La. R.S. 14:78) criminalize sexual relations with first cousins, adding penalties beyond marriage invalidity.
Legal Consequences
Void marriages trigger no divorce need but complicate property, children, and benefits. Bigamy charges arise if one party weds another unaware of the impediment.
Couples cohabitating face no bar, but offspring legitimacy requires separate paternity actions. Courts void benefits tied to spousal status.
Comparison to Neighbors
Texas and Mississippi allow first-cousin marriage with age caveats; Arkansas bans it outright. Louisiana aligns with strict Southern states on consanguinity.
Practical Guidance
Verify genealogy via records before licensing—clerks check IDs but not deep kinship. Genetic counseling aids informed choices for distant relations.
SOURCES:
- https://www.legis.la.gov/legis/Law.aspx?d=111053
- https://www.ulc.org/wedding-laws/louisiana
