Subject matter jurisdiction defines a court’s power to decide a lawsuit involving a particular subject matter, and to render an enforceable judgment. A court generally has jurisdiction when the particular claim raised in the case is within its constitutional jurisdiction—as provided by the state constitution or the U.S. Constitution—or because jurisdiction has been mandated by the state legislature or the United States Congress.

In Iowa, as in other states, subject matter jurisdiction refers to a court's authority to hear and decide cases of a specific nature. The Iowa Constitution, along with state statutes, outlines the jurisdiction of various courts within the state. For instance, the Iowa District Courts are the state's trial courts of general jurisdiction and have the authority to hear a wide range of cases, including civil, criminal, family, and probate matters. On the other hand, specialized courts such as the Iowa Court of Appeals and the Iowa Supreme Court have appellate jurisdiction, primarily reviewing the decisions of lower courts. Federal courts, such as the U.S. District Court for the Northern and Southern Districts of Iowa, have jurisdiction over matters involving federal law or disputes between parties from different states that meet certain monetary thresholds. The jurisdiction of each court is also defined by state and federal legislation, which can expand or limit the types of cases a court may hear. It is important for a court to have proper subject matter jurisdiction to render a legally binding and enforceable judgment.