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 Hawaii, a spouse seeking a divorce may do so on no-fault grounds, as Hawaii is a no-fault divorce state. This means that the spouse does not need to allege or prove the other spouse's fault as a basis for the divorce. Instead, the divorce can be granted on the basis of irretrievable breakdown of the marriage, where the spouses agree that the marriage cannot be salvaged. In no-fault divorce proceedings in Hawaii, the court does not consider fault when dividing marital or community property. However, allegations of fault may still play a role in other aspects of the divorce, such as determining spousal support and child custody. It is important to note that while fault is not a factor in the division of property, the conduct of the parties during the marriage may be relevant to the financial and child-related decisions the court makes.