I would have lit up my brake lights for him. Just the lights. If he didn't get the drift, then I'd slow down to about 5 mph.

YES, even knowing it was a cop I'd do this. If he pulled me over I'd ask him to radio for another cruiser to come and give him a ticket for following too close.

Keep in mind, I know where I live and I know how the police are around here. I wouldn't try this trick if I was traveling in some parts of the US. Too much chance of getting pulled out of the car and getting pistol-whipped in some places. :)

Bruno