Tyler and Katz, two judges, were each arrested on speeding charges. When they arrived in court on the appointed day, no one was there, so instead of wasting time waiting around they decided to try each other.  Motioning Tyler to the stand, Katz said, "How do you plead?"

"Guilty."

"That'll be fifty dollars and a warning from the court."

Katz stepped down and the two judges shook hands and changed places.  "How do you plead?" asked Tyler.

"Guilty."

Tyler reflected for a moment.  "These reckless driving cases are becoming all too common of late," he pointed out.  "In fact, this is the second such incident in the last quarter hour.  That'll be two hundred dollars and ten days in jail."