Canon 986

A person can exercise executive power over his subjects, even

though he himself is outside his own territorial boundaries and

even when they are outside his territory, unless common law provides otherwise or the contrary is certain from the nature of the

case; he can also exercise this power over travelers actually

present in his territory, provided it is a matter of granting

favors or of enforcing either common laws or particular laws by

which they are bound according to the norm of can. 1491, 3.