1. The police were in the opposite lane and must have locked on without sitting on the side of the road with a radar gun. I imagine they have some new stuff that uses their speed against an oncoming cars speed. Not hard to solve, but Ive never run into it before.
Running radar has been around a long time; 25 years at least. They also have a hand held device where the radar is on standby until they hit the button. It makes radar detectors useless. When I was a reserve cop I rode with guys who could tell how fast an oncoming car was going within a mile an hour before actually clocking the car.
On the Memphis highways they make a point of sitting on the side of the road and pointing the gun. I guess its more for show.
LIDAR