Jurisdiction is the official power or authority to make decisions, enforce rules, and handle legal matters in a particular area or over certain people. A judge has jurisdiction over the cases in their courtroom. A police officer has jurisdiction in the city or county where they work. A school principal has jurisdiction over what happens at their school.

Jurisdiction often depends on geography. A Texas state trooper has no jurisdiction in Oklahoma because their authority stops at the state border. A mayor has jurisdiction within city limits but not in neighboring towns. The Supreme Court has jurisdiction over the entire United States.

But jurisdiction can also depend on the type of situation. A family court judge has jurisdiction over adoption cases but not over criminal trials. Your school principal has jurisdiction during school hours and at school events, but not over what you do at home on weekends.

When someone acts “outside their jurisdiction,” they're trying to use authority they don't actually have. Understanding jurisdiction helps explain why certain people can make certain decisions while others can't.