A juggler, driving to his next performance, was stopped by the police. 

"What are those knives doing in your car?" asked the officer.

"I juggle them in my act."

"Oh yeah?" says the cop. "Let me see you do it."

So the juggler starts tossing and juggling the knives.

A guy driving by sees this and says to his buddy, "Wow, am I glad I quit 

drinking. Look at the test they're making you do these days!"