The Supreme Court has paid a significant amount of attention to federal subject matter jurisdiction in the last few terms. Commentators have followed the Court's lead with a flood of articles discussing the merits of the Court's jurisdictional rulings and extending the law to areas the Court has not (yet) reached. The debate has touched on fairness, history, and the institutional roles of the courts and the legislature.

Oddly missing from the entire discussion has been the Constitution. This is understandable because jurisdictional issues are usually presented as statutory questions: Congress has the power to determine how much jurisdiction to actually grant to the federal courts, up to the jurisdictional ceiling created by Article III. So whether a federal court has jurisdiction is often a question of whether Congress has granted jurisdiction, rather than whether the Constitution permits Congress to do so. The constitutional ceiling lurks in the background of jurisdictional questions, yet it has been ignored in the recent debates about subject-matter jurisdiction.

This Article aims to fill this gap in the debate by re-examining the constitutional constraints. I argue that structural limitations on the extent of congressional power should be treated as limitations on the scope of the federal courts' jurisdiction under the clause of Article III that grants courts the power to hear cases "arising under ... the Laws of the United States." In other words, I show that the powers exercised by these coequal branches of government are coextensive. While this thesis may sound quite natural, the federal courts have apparently not thought it to be true.