Incest Laws by State [Updated May 2023]

Incest is defined as a sexual relationship between two closely related family members. The relationship between the two people is so close that they are unable to legally get married. In the United States, incest laws prohibited intimate relationships between children and parents, siblings, or grandchildren and grandparents. Almost all states criminalize incest between adults. Some states also prohibit intimate relations between aunts, uncles, nieces, nephews, and cousins. Additionally, state laws vary regarding half- and step-relatives and adopted relatives. States also have minimum age laws for marriage to help prevent child marriage, which could help prevent incestuous relationships.

In the majority of states in the United States, incest is illegal. The punishments associated with engaging in an incestuous relationship vary by state. In many cases, incest is not revealed to outside parties, so the parties involved are not prosecuted. Except for those states mentioned below in this article, incest is illegal in all states.

In the states of New Jersey and Rhode Island, incest between adults is legal. However, neither state permits marriage. In New Jersey, each person involved in the relationship must be at least 18 years old. In Rhode Island, the age of consent is 16 years old.

Delaware has the lowest maximum sentence for being convicted of incest, one year. The majority of states have maximum sentences of five to fifteen years. The harshest sentences are in Idaho, Kentucky, Montana, and Nevada. In these states, a person faces a maximum sentence of life in prison.