international courthouse
A court of law with international jurisdiction, usually legitimized by treaties between countries.
An international courthouse is a court of law whose jurisdiction transcends national boundaries. These may be administered by the United Nations or set up with authority derived from international treaties.
This usage should be applied to any court with international jurisdiction extending to more than 3 countries, regardless of whether it focuses on general law or specific types of cases (e.g. criminal).
The jurisdiction must extend to more than three countries. That international scope takes precedence over specialization in one kind of case, including criminal cases; a court hearing only domestic cases is not made international by the nationality of a party.