I looked into flying for the Oklahoma Sate Highway Patrol back in the late 80's. They flew a few Single engine types and a King Air for the Gov. When I was looking into it they told me that you had to be a trooper (like mentioned above) and that I would have to spend 5 YEARS on the ground in a patrol car before I could even look into the aviation unit - no matter what qualification you held.

USMCFLYR