As a practical matter, who would patrol railroad property if there were no railroad police? At this point non-railroad police working in Richmond, California (as a typical example), often do not even know what railroad runs on a specific track. They get completely baffled by location and directions when dealing with incidents along a rail line. Clearly, this is also a problem in many other places. Non-railroad cops have no training in railroading at all. That lack of knowledge creates a safety issue for those police and would likely make any sort of patrol of railroad property useless.

I recall when BART was forming and they had no plans for a police force. No city or county jurisdiction would touch BART. So they had to form their own police force. I'm sure BART cops have specialized training in areas that non-BART cops do not. Another example: NYC transit police, a large force, are track certified; otherwise they could quickly get killed by a train on that busy railroad.

It would seem the present system of railroad cops who know their railroad and have not only the standard police training but specialized instruction in rail operations and safety works well. UP cops are a really thin blue line, but essential, as I cannot envision any other agency taking over their tasks. Not even the TSA, which provides so much free security for aviation on the taxpayer dollar, would be up to handling the job.