Seems St. Peter and the Devil had an agreement to share the costs of maintaining the fence between Heaven and Hell.
One weekend there was a bit of a brawl in Hell that got out of hand, and part of the fence was smashed. It went unfixed for weeks and St. Peter approached the Devil about mending it.
Nothing happened over the period of a month.
Finally, in exasperation, St. Peter said he would sue the Devil if he didn't pay up.
"Oh" retorted the Devil, "and where are you going to find a lawyer?"