There was this guy who was cleaning a court house in the USSR when he heard someone laughing loudly in the otherwise empty building - he discovered that it was a judge in one of the court rooms.
He asked him what was so funny. The judge said: "One of the suspects I just sent to the Gulag told us a really funny joke" - "Would you mind sharing it with me?" - "No, I can't do that or I will also have to send you to the Gulag".