Late one Friday night, a policeman spotted a man d

Late one Friday night, a policeman spotted a man driving 
very erratically through the streets of Dublin. They 
pulled the man over and asked him if he had been 
drinking that evening."Aye, so I have. It's Friday, you 
know, so me and the lads stopped by the pub where I had 
six or seven pints. And then there was something called 
"Happy Hour" and they served these mar-gar-itos which 
are quite good. I had four or five of those. Then I had 
to drive me friend Mike home and of course I had to go in 
for a couple of Guiness - couldn't be rude, ye know. Then 
I stopped on the way home to get another bottle for later..." 
Then, the man fumbled around in his coat until he located 
his bottle of whiskey, which he held up for inspection. 
The officer sighed, and said, "Sir, I'm afraid I'll need 
you to step out of the car and take a breathalyzer test." 
Indignantly, the man said, "Why? Don't ye believe me?!"