Not sure how they do it in Ohio, but they've been doing this in Missouri for a while. They post the signs right before an exit that is rarely used that say some

Not sure how they do it in Ohio, but they've been doing this in Missouri for a while. They post the signs right before an exit that is rarely used that say something like "Drug checkpoint ahead be prepared to stop." I think I even saw it say something like last exit before checkpoint once. They then stop everyone that gets off at the exit. If you take a second to think about it, it's pretty obvious. Apparently it still manages to catch people.