Caught in the Act

A guy is walking home late at night and sees a woman in the shadows. “Twenty dollars” she whispers.
He had never been with a hooker before, but decides what the hell, it’s only twenty bucks. So they hide in the bushes.
They’re going at it for a minute when all of a sudden a light flashes on them. It’s a police officer. “What’s going on here, people?” asks the officer.
“I am  making love to my wife, officer” answers the guy sounding annoyed.
“Oh I am sorry,” says the cop, “I didn’t know.”
“Well, neither did I until you shined that light in her face.”