This officer who is a friend of mine and owns a blinder himself was nice enough to meet up with us to test my friends BMW 3 series with his Blinder M45 and escort ZR3's. The officer could not get anything on the front, so he took a shot at the cars A-Frame which is just above the drivers side mirror, and got a target lock at 500 feet.
This just comes to show that some officers can target any part of your car if they are having trouble getting a target lock on the front. Thats why I recommend you slow down and turn the jammers off. Let the officer do his job. YouTube - Real world testing vs. ProLite