USATODAY.com - Fake checkpoints OKed in hunt for motorists' illegal drugs: " Colorado police can set up fake checkpoints in hopes of sniffing out illegal drugs, an appeals court ruled in a case where camouflage-clad officers spied on fans during a bluegrass festival in 2000. "
I'm not quite sure what I think of this. It had previously been ruled illegal for police to set up random checkpoints to search cars for drugs. This case was about a fake checkpoint, where the police put up signs saying "Narcotics Checkpoint Ahead". There was, in fact, no checkpoint. There were police in concealment watching the road near the signs and stopping people who threw things out of their car when they saw the sign. In the particular case, the police found a marijuana pipe that had been thrown out of the car and used that as a justification for searching the car.