The question of whether the court has subject matter jurisdiction frequently arises when counsel has to decide whether to bring a support or custody proceeding in the Supreme Court or the Family Court. A judgment or order made without subject matter jurisdiction is void. The defect may be raised at any time and may not be waived. Lacks v. Lacks, 41 N.Y.2d 71 (1976). Bringing an action in a court that lacks subject matter jurisdiction will result in dismissal.

Subject matter jurisdiction has been defined as the "power to adjudge concerning the general question involved,…." It does not depend upon the existence of a good cause of action. It is the power to deal with the subject involved in the action. Hunt v. Hunt, 72 N.Y. 217, 229 (1878). There is a distinction between a court's competence to entertain an action and its power to render a judgment on the merits. "The absence of competence to entertain an action deprives the court of subject matter jurisdiction; the absence of power to reach the merits does not." Thrasher v. United States Liab. Ins. Co., 19 N.Y.2d 159 (1967).

The Supreme Court is a court of general jurisdiction, and it is competent to entertain all causes of action unless its jurisdiction has been specifically proscribed. Id. It is endowed with general original jurisdiction in law and equity. N.Y. Const., art. VI, §7, (a). Its subject matter jurisdiction may only be preempted under the Supremacy Clause of the U.S. Constitution. U.S. Const., art. VI, cl. 2; Doomes v. Best Transit, 17 N.Y.3d 594 (2011).