Third Party Practice Law and Legal Definition

Third party practice is a procedural devise by which a defendant in an action brings an additional party in a claim asserted against him/her. Rule 14 of Rules of Civil Procedure for the District Courts of the U.S. lays down the procedure for third party practice.

The purpose of third-party practice is to avoid circuity and multiplicity of actions or suits; and to adjust in a single action, the several phases of the same controversy. [(Masters v. Hart, 189 Va. 969 (Va. 1949)]