It seems that we have no problem accepting "driverless cars" but we take for granted that police/traffic enforcement will always be done by humans and will only

It seems that we have no problem accepting "driverless cars" but we take for granted that police/traffic enforcement will always be done by humans and will only use sloppy human verbal/hand4ignal communication. From all the "slow down my mommy works here" road signs it seems roadside construction is dangerous. Why not use robotic traffic directors? And/or supplement the human with some technology.