Scotch law. A writing drawn up in the form of a petition, called a bill of advocation, by which a party in an action applies to the supreme court to advocate its cause, and to call the action out of an inferior court to itself. Letters of advocation, are the decree or warrant of the supreme court or court of sessions, discharging the inferior tribunal from all further proceedings in the matter, and advocating the action to itself. This proceeding is similar to a certiorari issuing out of a superior court for the removal of a cause from an inferior.