If a marriage is annulled, it is declared a legal nullity, meaning that it never existed. Grounds for annulment vary from state to state, as it does for most areas of domestic relations laws. Common examples include when a party lacked the capacity to consent to marriage through mental infirmity or when one party was under the influence of alcohol or drugs. A marriage can be annulled if one party obtained consent from the other party through force or fraud. A marriage also can be annulled if one party lacks the physical ability to consummate the marriage (have sexual relations) and the other party did not know of this problem. A marriage also can be annulled if one party was under the age of consent as defined by applicable state law.