A guy had been drinking half the night by the time the bar closed.  After spending a while trying without luck to put the key in the ignition, he realizes that he's in absolutely no shape to drive.

So he leaves the car parked & begins walking very unsteadily toward home.  Along the way he's stopped by a cop who asks, "Where doing out on the street at 2AM?"

"I'm going to a lecture," the guy replied.

"And who is going to be giving a lecture at this hour?" asks the cop.

"My wife."