CHP officers on Highway 58 routinely monitor cars and radio ahead to other officers to pull speeders over. A recent Delaware case indicates that this common practice may be illegal.
In State v. Nyala, an officer claimed that he saw Mr. Nyala make a right turn without signaling. Other officers pulled him over for the traffic violation, although they did not actually see him make the illegal turn. The court overturned the stop, saying that the officers did not have probable cause.
Delaware does have an exception that allows officers to radio ahead to stop people who are speeding, running a red light, talking on a cell phone or not wearing a seat belt, but the court's analysis suggests that these exceptions may be short lived.
Here in California, remote traffic stops are still used routinely. The most common situation is where one officer picks off motorists with a LIDAR gun and radios to waiting officers on an off ramp or in another close by place. CHP planes still nab people from the skies and send officers to pull them over.
There are several different ways that you can beat a ticket in California that involves a remote stop. Talk to an experienced traffic lawyer about what you can do to maximize a ticket that you received on that trip to Las Vegas.