There are two distances in traffic and transportation engineering.
1. Stop sight distance - the distance that an upcoming driver detecting you (ususally your vehicle front bumper tip)
2. Corner sight distance - the distance from the spot where you pull your car out to the upcoming vehicles you detect.
Since there is couple of feet from your driver's seat to your front bumper, that means there is possibility that the cop can see you while you cannot see him.
Hope that helps.
