"What's the Going Rate for Bribing a Traffic Cop?":

I am told that the top and bottom limit in the United States is $100. No need to offer more; don't bother offering less. The delicate issue, of course, is how it's proffered. Best defense: Let it fall "absentmindedly" to the ground as you pull out your driver's license (don't look at the money). You haven't offered anything; it's the cop's choice to pick it up after you leave. But as with any bribe, you could lose your $100, get nailed for the ticket and wind up in county jail.