In the Catholic Church, a declaration of nullity, commonly called an annulment and less commonly a decree of nullity, and in some cases, a Catholic divorce, is an ecclesiastical tribunal determination and judgment that a marriage was invalidly contracted or, less frequently, a judgment that ordination was invalidly conferred.
A matrimonial nullity trial, governed by canon law, is a judicial process whereby a canonical tribunal determines whether the marriage was void at its inception (ab initio). A "Declaration of Nullity" is not the dissolution of an existing marriage (as is a dispensation from a marriage ratum sed non consummatum and an "annulment" in civil law), but rather a determination that consent was never validly exchanged due to a failure to meet the requirements to enter validly into matrimony and thus a marriage never existed.