How can transient jurisdiction allow a U.S. court to hear a case against a visitor?

In the United States, transient jurisdiction allows a court to hear a case against a visitor based on the principle of physical power over the defendant. Under this rule, a court may assert jurisdiction over an individual if they are served with legal documents commencing a lawsuit while physically present within the territory of the state where the court is located.1

This applies even if the defendant is only in the state temporarily or is merely passing through in transit. Because this practice favors plaintiffs by allowing them to initiate litigation in a forum where they have successfully served the defendant, it is categorized as an "exorbitant" rule of jurisdiction. While common-law countries like the U.S., the United Kingdom, and Ireland utilize this basis for jurisdiction, it remains a point of international tension, as many civil-law jurisdictions rely instead on the defendant's domicile or a specific connection between the dispute and the forum.1