Rather than using the term “annulment,” Montana law provides for a declaration of invalidity. If a marriage is declared invalid, it is basically as though the marriage never occurred.
Under Montana law, there are only certain circumstances under which a declaration of invalidity is possible. For example, invalidity is appropriate when one of the parties to the marriage lacked the capacity to consent to the marriage either because of the influence of alcohol/drugs or because they have some sort of mental disease or defect that makes them unable to consent. If a party was forced into the marriage or induced by fraud, the court may declare the marriage invalid.
Another circumstance where the court may declare a marriage invalid is if one of the parties to the marriage lacks the physical capacity to consummate the marriage and the other party was not aware at the time of the marriage.
Age can also be a reason that marriage is declared invalid. If one or both of the parties was under 16 years of age at the time of the marriage, the court will likely declare the marriage invalid. If one or both of the parties was 16 or 17 years old, but failed to obtain a parent’s consent or the consent of the court, the marriage is likely invalid.
Finally, if the marriage is prohibited, it will likely be declared invalid. For example, if one party is already legally married, an additional marriage is prohibited by law. Marriages between relatives are prohibited by law as well.
Because Montana’s invalidity law is very fact based, anyone considering filing a petition for declaration of invalidity should speak with an attorney about their rights.