Intergalactic law

Miniscopes were expressly forbidden by intergalactic law. (TV: Carnival of Monsters)

The Sixth Doctor told H.G. Wells, who had stowed aboard his TARDIS that there was an intergalactic law expressly forbidding stowaways. (TV: Timelash)

Eden 2 was a virtual level 1 planet used to lure in would-be conquerors and impose the punishments of intergalactic law upon them. The Vladlack were sentenced to a thousand years hard labour for their invasion attempt. (COMIC: Freeze)