Alienation of affection and criminal conversation are potential legal claims or causes of action against a person who committed adultery with your spouse—the paramour or lover with whom your spouse had an affair. These claims are based on the idea that the person with whom your spouse cheated destroyed or alienated the love and affection in your marriage.

Alienation of affection claims are no longer recognized by courts in most states—but Hawaii, Mississippi, New Mexico, North Carolina, South Dakota, and Utah do recognize such claims. And in some states that do or do not not recognize such claims, the cheated-on spouse may seek an unequal division of the marital estate based on fault in the breakup of the marriage.

The details of alienation of affection laws (sometimes called heart-balm laws) vary from state to state among the states that do recognize such claims.

In South Dakota, the claim of alienation of affection is recognized and can be brought against a third party, typically the paramour, who has engaged in conduct that results in the loss of affection in a marriage. This cause of action is based on the premise that the third party's actions have interfered with the marital relationship, leading to its deterioration. South Dakota is one of the few states where such claims are still permissible, as many states have abolished this type of lawsuit. The specifics of how these claims are handled, including the types of evidence required and potential defenses, are governed by state statutes and case law. Additionally, in cases of divorce, South Dakota courts may consider adultery and other fault-based reasons for the breakdown of the marriage when deciding on the division of the marital estate. An attorney can provide detailed guidance on the likelihood of success with an alienation of affection claim and the impact of adultery on divorce proceedings in South Dakota.