You may laugh at a mid-day sobriety checkpoint. They set them up along the interstates here in Georgia. I was heading to the girlfriend's condo on the Georgia coast Memorial day weekend. I was on I-77 south and saw a mobile electronic road/announcement sign saying "DUI Checkpoint Ahead...All Vehicles." My first thought was "not on an interstate". Well, they had the checkpoint set up on one of the exits. I saw at least 5 cars bite for it and there must have been another 10 cars waiting in line....on top of every police vehicle in the county. Everyone in the left lane just breezed on by at 80 mph. There was no one making you pull over and there were no police cars directly at the beginning of the exit. I later heard that that exit/county nabbed 200 drunk drivers that Friday alone.
And, I went to school in the (sic) great state of Alabama - Auburn University. Never saw a DUI checkpoint, but they did make me take a DUI test when I turned in front of a car with no headlights on at 1:00 am. I asked what I was being pulled over for. The officer said failure to yield because I turned left in front of a car. I said, the one I saw at the last second b/c they didn't have their lights on? He said yes...I pulled you over b/c you were closest. Of course, I passed the test with flying colors. And, the ticket got dropped because I appealed and the officer was on tape/video admitting I had unwhittingly turned in front of a vehicle w/o headlights on.