Stopping cars on foot

hello people of gpm (excluding ray)

Is there anyway 2.0 can include the ability to stop cars on foot? For example, I want to have a DUI checkpoint however I cannot stop cars on foot to breathalyze them. I'd have to have someone in a car, initiate the stop, then wait for them to pull over somewhere down the road, not in the checkpoint. Or maybe the ability to use the breathalyzer / drug stuff without stopping the ped?