The drug check sign ahead is to give the police probable cause to search the vehicle. There will be a checkpoint and they may ask you if you have any drugs but what they really want is for you to pull a u-turn after seeing that sign and there will be additional cops waiting to spot you doing this “because you did it after seeing the sign” so now they have probable cause to pull you over and search based on suspicion of drugs.
“There will be a checkpoint and they may ask you if you have any drugs but what they really want is for you to pull a u-turn”
My comment was meant to convey why do they have any check points? Why if they do have them don’t they have them for say “citizenship check”. Or, how about they decide to have a “rape check point or Kidnap check point” so they can check to be sure everyone in the car is there of their own accord? Our police state has gone too far and yet not in the right directions IMO.