The Designated Decoy

Recently a routine police patrol parked outside a bar in western North Carolina.  After last call the officer noticed a man leaving the bar so intoxicated that he could barely walk.

The man stumbled around the parking lot for a few minutes, with the officer quietly observing. After what seemed an eternity in which he tried his keys on five different vehicles, the man managed to find his truck and trailer and fall into it. He sat there for a few minutes as a number of other patrons left the bar and drove off.

Finally, he got into the car and started the engine, switched the wipers on and off - it was a fine, dry summer night, flicked the blinkers on and off a couple of times, honked the horn and then switched on the lights. He moved the vehicle forward a few inches, reversed a little and then remained still for a few more minutes as some more of the other patrons' vehicles left. At last, when his was the only car left in the parking lot, he pulled out and drove slowly down the road. 
The police officer, having waited patiently all this time, now started up his patrol car, put on the flashing lights, promptly pulled the man over and administered a breathalyzer test. To his amazement, the breathalyzer indicated no evidence that the man had consumed any alcohol at all! Dumbfounded, the officer said, 'I'll have to ask you to accompany me to the police station. This breathalyzer equipment must be broken.' 
 
'I seriously doubt it', said the truly proud hillbilly. 'Tonight I'm the designated decoy.'