The woman in question, a cute blonde as it happens, was pulled over for speeding by a California Highway Patrol motorcycle officer. When he walked up to her window and opened his ticket book she said: "I bet you're going to sell me a ticket to the Highway Patrolmen's Ball."
He replied, "No, highway patrolmen don't have balls."
There followed a moment of silence while she smiled and he realized what he'd said.
He then closed his book, got back on his motorcycle and left.