personal jurisdiction

Personal jurisdiction is a court's jurisdiction over the parties to a lawsuit, as opposed to subject-matter jurisdiction, which is jurisdiction over the law and facts involved in the suit. If a court does not have personal jurisdiction over a party, its rulings or decrees cannot be enforced upon that party, except by comity, that is, to the extent the sovereign that does have jurisdiction over the party allows the court to enforce them upon that party. A court that has personal jurisdiction has both the authority to rule on the law and facts of a suit and the power to enforce its decision upon a party to the suit. In some cases, territorial jurisdiction may also constrain a court's reach, such as preventing hearing of a case concerning events occurring on foreign territory between two citizens of the home jurisdiction.