The Golden Rule, at least in its usual formulation, would seem to be problematic in cases of justice. If a judge were to "Do unto others as you would have them do unto you", then they would probably never sentence anybody. A teacher couldn't fail a student who tried very hard because, presumably, that teacher (at least as a student) would have preferred a barely passing grade if they had tried very hard.
The only way around this seems to be for people to enthusiastically and voluntarily be willing to punish themselves, which seems a bit of a stretch, to say the least; at most, people recognize that some system of rules requires they be punished and, perhaps, that system has a point, but nobody really *wants* to be punished.
So how do proponents of the Golden Rule deal with such cases? Must they search elsewhere for their justification, or do they change the scope or meaning of the Golden Rule?