A farmer got pulled over by a state trooper for speeding, and the
trooper started to lecture the farmer about his speed, and in general
began to throw his weight around to try to make the farmer
uncomfortable.

Finally, the trooper got around to writing out the ticket, and as he
was doing that he kept swatting at some flies that were buzzing
around his head.

The farmer said, "Having some problems with circle flies there, are
ya?"

The trooper stopped writing the ticket and said - "Well, yeah, if
that's what they are, I never heard of circle flies".

So the farmer says- "Well, circle flies are common on farms. See,
they're called circle flies because they're almost always found
circling around the back end of a horse."

The trooper says, "Oh," and goes back to writing the ticket. Then
after a minute he stops and says, " Hey---wait a minute, are you
trying to call me a horse's behind?"

The farmer says, "Oh no, officer. I have too much respect for law
enforcement and police officers to even think about calling you a
horse's behind."

The Trooper says, "Well, that's a good thing," and goes back to
writing the ticket.

After a long pause, the farmer says, "Hard to fool them flies though."