Most states don't like local cops patroling the Interstate highways, but they do. About 8 years ago, Texas passed a law that if local police set up speed traps on Texas state highways, they could not keep the fines, they could only keep a small $15-$20 administration fee. That forced on small town that ran a 24 hour speed trap just a few miles outside of Fort Hood, TX to go broke and fired their whole police department. Nearly 90% of the revenue was coming from their speed traps.
Oddly enough, many of the cities and towns are in financial straits and ignoring the law by setting up speed traps on the Interstate. What they do is set up speed traps and charge higher fines and then don't report them to the state of Texas. I got a ticket about 3.5 years ago in Texarkana, TX when the speed limit was reduced from 70 MPH to 60 MPH as you got within the city limits. The fine was over $200, which I paid. That ticket was never reported to the State and has never been recorded on my drivers license and I have never been assessed any points for that ticket??? That's when I figured out what they are doing.
Even when the local police are within their juristictions, they are setting up a lot more speed traps to boost the town's revenue.
Last weekend I went to Dallas and during my 100 mile return trip on I-35, I must have seen at least 10 cops who had already pulled someone over, and only about half of them were State Police...That's not to mention the number of local cops I spotted hiding just over the crest of a hill, etc
I agree with Caymen's statement...They are using tickets to increase their revenue, not to improve safety. I also know that cops will give tickets on toll roads...The fact that you pay extra to use the road does not mean you are allowed to speed. If there is a speed limit sign, you can be ticketed if you exceed it.
....Rich