Most states allow spouses seeking a divorce to allege fault in the breakup of the marriage as a basis for the divorce. Alleging the other spouse’s fault—rather than seeking the divorce on no-fault grounds (irreconcilable differences or incompatibility, making the marriage unsustainable)—is generally a basis for requesting the court make an uneven distribution of the marital or community property in favor of the spouse alleging the other’s spouse’s fault.

In states that allow a spouse to seek a divorce on fault grounds, the grounds that may be alleged vary from state to state, but generally include adultery, cruelty, conviction of a felony, family or domestic violence, abandonment, mental illness, and substance abuse (drugs and alcohol). Spouses may also seek a divorce on no-fault grounds in these states.

In no-fault states, a spouse is not allowed to allege fault as grounds for the divorce, and the court is not allowed to consider fault in dividing the marital or community property—but allegations of fault may be considered for other purposes, such as spousal support and child custody. No-fault states include California, Colorado, Florida, Hawaii, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, Oregon, Washington, and Wisconsin. And in some states “incurable insanity” is a no-fault ground for divorce.

The grounds on which a spouse may seek a divorce (fault or no-fault) are usually located in a state’s statutes—often in the family code or domestic relations code.

In New Mexico (NM), spouses seeking a divorce have the option to file on either fault or no-fault grounds. No-fault divorce is based on incompatibility, which means that the spouses agree that their marriage cannot be sustained due to irreconcilable differences. On the other hand, New Mexico also allows for fault-based divorces, where one spouse can allege specific grounds for the divorce such as adultery, abandonment, cruel and inhuman treatment, and others as defined by state statutes. While New Mexico is not exclusively a no-fault state, the court may consider fault when deciding on issues such as the division of marital property, spousal support, and child custody. However, the preference for no-fault divorces reflects a general trend towards recognizing that marriages may end without specific fault, aiming to reduce the conflict and complexity involved in divorce proceedings.