Guy going home from the pub is stopped at a police checkpoint. A bobby comes over and tells the driver to roll down his window. When he does, the copper is almost knocked over with the smell of alcohol. So he asks: "Have you been drinking, suuur?" (as English cops are wont to say). "Yes", replies the driver. "What did you have exactly, suuuur"? "Well, about seven or eight pints of Guinness, a couple of whiskies, and then one or two night caps in the form of double brandies". The copper pulls out his breathalyzer and says, "Would you mind blowing into this, suuur"? To which the drunk dude retorts: "What for? Do you not believe me?"