In the scene where Newman and Kramer are in court, the judge calls Newman "Mr. Newman". To my knowledge, Newman's last name has never been revealed, but I doubt his full name is Newman Newman. It seems like a mistake to me. COMMENT: I doubt we were ever to think of "Newman" as a first name. He is called by his last name in the same way that Kramer is. The judge calling him "Mr. Newman" confirms that.