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.

Wisconsin is a no-fault divorce state, meaning that a spouse cannot allege fault as grounds for divorce. The only basis for divorce in Wisconsin is the irretrievable breakdown of the marriage, where the court finds that the marriage is irreparably broken and there is no chance of reconciliation. This is outlined in Wisconsin Statutes Section 767.315. As a no-fault state, when it comes to the division of marital property, the court does not consider fault. Instead, the division is based on a presumption of equal distribution, but the court may alter this distribution based on factors such as the length of the marriage, the property brought to the marriage by each party, and the contributions of each party to the marriage, among others, as per Wisconsin Statutes Section 767.61. However, allegations of fault may still play a role in other aspects of the divorce proceedings, such as spousal support and child custody determinations, where the best interests of the child are paramount.