This definitely a speed trap. Fact: if you are black with a California license plate you will be stopped. You can receive a ticket and a quarter mile down the road, get stopped again. These officers always use the seatbelt excuse, even when you are wearing a seatbelt. This is order of reasoning for stopping, 1) Seatbelt 2) speeding 3)speeding in construction zone, if though there are no orange signs or cones anywhere on interstate. 4) if you are a minority, they will pull over a non minority behind you, but never make them exit the vehicle, interview them or ticket them (they are stopped to make them stopping you legitimate.