You should never talk to any police officer under any circumstances. Why not? Take it away, Professor James Duane:
If there were any justice, this guy would be appointed Emperor of the Milky Way. Thanks to commenter Willy at A Tiny Revolution for pointing out this unbelievably cool video.
If you just can't get enough of this civil rights stuff, see also the worthwhile (but longer and far less entertaining) "Citizen's Guide to Surviving Police Encounters" here, or the related and very useful FAQ here.
Finally: I'm about to start following a bunch of tuneful Scotsmen across the country and then quite possibly looking at water and dirt, so posting will be light to nonexistent for a while. In the meantime, feel free to watch this excellent video not once, not twice, but thrice.
[ NOTE: This posting contains three fun hidden contests! The winners of two of them will receive the award of having impressed me by figuring them out, which is admittedly a sucky prize. As for the third, I'd be very happy if nobody wins it, though my experience with human nature doesn't make me hopeful; the winner, should one come forward, will receive a coveted "most illogical person on the planet" award. ]