The power of a court to adjudicate a particular type of matter and provide the remedy demanded.
A court must have jurisdiction to enter a valid, enforceable judgment on a claim. In fact, litigants, through various procedural mechanisms, have the capacity to retroactively challenge the validity of a judgment where jurisdiction was lacking.
Jurisdiction may be broken down into two categories: personal jurisdiction and subject matter jurisdiction. Personal jurisdiction is the constitutional requirement that a defendant have certain minimum contacts with the forum in which the court sits so that said court may exercise power over the defendant. Subject-matter jurisdiction is the requirement that a given court have power to hear the specific kind of claim that is brought to that court. While litigating parties may waive personal jurisdiction, they may not waive subject-matter jurisdiction. In federal court, under the Federal Rules of Civil Procedure, a motion to dismiss for lack of subject-matter jurisdiction is considered a favored defense and may be raised at any point in the litigation process. In fact, the court may dismiss a case sua sponte—or, on its own—for lack of subject-matter jurisdiction. See, e.g., Fed. R. Civ. Proc. 12(b)(1).
The requirement that a court have subject-matter jurisdiction means that the court can only assume power over a claim that the laws of the jurisdiction authorize it to hear. For example, Congress limited the subject-matter jurisdiction of the United States Tax Court to cases related to taxation; thus, that court does not have subject-matter jurisdiction over any other matter. Most state courts are courts of general jurisdiction. That is, state courts are presumed to have power to hear virtually any claim arising under federal or state law, except those falling under the exclusive jurisdiction of the federal courts. However, for pragmatic reasons some states deny subject matter jurisdiction to specific claims, such as those arising in other states. In addition to courts of general jurisdiction, most states also maintain specialized courts of limited subject-matter jurisdiction. Examples of these types of courts include probate courts, traffic courts, juvenile courts, and small claims courts.
As opposed to state courts of general jurisdiction, federal courts are courts of limited jurisdiction. Thus, with few exceptions found in the Constitution itself, Congress defines the subject-matter jurisdiction of the federal courts. In order to bring an action in federal court, the plaintiff must find a constitutional or congressional grant of subject-matter jurisdiction to allow the federal court to hear the claim. See U.S. Const. Art. III, Sec. 2. As a general rule, courts read congressional grants of subject-matter jurisdiction narrowly, resolving any ambiguities in favor of denying jurisdiction.
A threshold concern for all federal courts is the presence, or absence, of constitutional standing. The standing requirement, as governed by Article III of the Constitution, permits federal courts to adjudicate only cases or controversies. A case or controversy must comprise an actual injury, which is traceable to a defendant and susceptible to judicial redress. See Lujan v. Defenders of Wildlife. Subject-matter jurisdiction does not exist in the absence of this constitutional standing. By restricting the reach of federal courts to actual disputes, the standing requirement prevents politically unaccountable courts from influencing the law in a legislative capacity. In this sense, the standing doctrine and subject-matter jurisdiction facilitate the separation of powers.
The two primary sources of the subject-matter jurisdiction of the federal courts are diversity jurisdiction and federal question jurisdiction. Diversity jurisdiction generally permits individuals to bring claims in federal court where the claim exceeds $75,000 and the parties are citizens of different states. See 28 U.S.C. § 1332. So, if a citizen of New York sues a citizen of California for more than $75,000, a federal court would have subject-matter jurisdiction to hear that claim. Under federal question jurisdiction, a litigant—regardless of the value of the claim—may bring a claim in federal court if it arises under federal law, including the U.S. Constitution. See 28 U.S.C. § 1331. Federal question jurisdiction requires that the federal element appears on the face of a well-plead complaint, is a substantial component of the complainant's claim, and is of significant federal interest. Federal question subject-matter jurisdiction is frequently derived from federal statutes granting a cause of action to parties who have suffered a particular injury. Furthermore, it is important to note that 28 U.S.C. § 1367 provides for supplemental jurisdiction in federal courts. Supplemental jurisdiction allows a federal court to adjudicate a claim, over which it would not have subject-matter jurisdiction independently, on the basis of that claims connection to a related claim over which the federal court does have jurisdiction.
The jurisdictional division between state and federal tribunals is an essential component of American federalism. Federal courts possess exclusive jurisdiction over certain subject matter, notably those issues of national significance like patent and admiralty law. See U.S.C. §§ 1333, 1338. Exclusive jurisdiction over such issues is indicative of a salient federal interest in particular subject matter and allows for the development of a uniform body of federal law governing complex issues with interstate implications. Conversely, the limited jurisdiction of federal courts encourages resort to local tribunals when adjudicating issues germane to those courts. This also inhibits excessive federal judicial intervention. Moreover, federal and state tribunals have subject-matter jurisdiction, concurrently, over a great many issues. This is reflective of the integrated judicial system present in the United States.
Finally, it is important to recognize the far reaching jurisprudential impact of the concept of subject-matter jurisdiction. While discourse in the United States surrounding subject-matter jurisdiction is often related to the relationship between domestic courts, subject-matter jurisdiction plays an operative role in the international sphere as well. Issues frequently arise, for example, involving the jurisdiction of international criminal tribunals, like the Special Tribunal for Lebanon. In these debates subject-matter jurisdiction takes on international political significance as parties must decide the degree to which a supranational tribunal can affect persons traditionally subject to domestic law.