Each state’s constitution and laws establish the state’s courts, which interpret state laws (and generally not federal laws). A court of last resort, often known as a supreme court, is usually the highest court in the state. Some states also have an intermediate court of appeals. Below these intermediate courts of appeal are the state trial courts, where most lawsuits begin. State trial courts are referred to differently in different states—often as district courts, circuit courts, or superior courts.

State courts are often courts of general jurisdiction—meaning they hear all types of cases—involving criminal law, family law, probate law, and general disputes involving money and property. But more populated counties often have courts of specific jurisdiction, such as family courts that only hear family law matters (divorce, child custody, child support); criminal courts that only hear criminal matters; and probate courts that only handle the probate of estates and related litigation.

In Massachusetts, the judicial system is structured with the Supreme Judicial Court at the apex, serving as the state's highest court with the authority to review decisions from lower courts and interpret state laws. Below the Supreme Judicial Court is the Massachusetts Appeals Court, which is an intermediate appellate court that reviews decisions from trial courts. At the base level are the trial courts, which include the Superior Courts, District Courts, Probate and Family Courts, Housing Courts, Land Court, and Juvenile Courts. These trial courts have general jurisdiction and handle a wide range of cases, including criminal, civil, family, housing, and probate matters. However, some courts, like the Probate and Family Courts, Juvenile Courts, and Housing Courts, have specific jurisdiction over certain types of cases. For example, Probate and Family Courts deal exclusively with matters such as divorce, child custody, and estate issues, while Juvenile Courts handle cases involving minors. The Massachusetts court system is designed to ensure that there is a clear hierarchy for appeals and that specialized matters can be addressed by courts with the appropriate expertise.