Then you get into mass-transit and it gets messy...
New Jersey is a lot of fun cause of the NJTransit Police. See...NJTransit is a quasi-public corporation. It's funded partly by tax-dollars and answers to the state budget office, but is not part of the state DOT, and is not directly governed by the legislature. Complicated huh? Gets better...
NJTPD is responsible for enforcement and protection of NJTransit policies and properties, buuuuuuut by oath and authority basically State Troopers that are in no way associated with the state police, nor county or municipal agency. They are a sworn public department, serving a corporate entity. And they are all out. NJTPD has their own FBI trained dedicated counter-terrorism/surveillance unit, SWAT team, detective bureau, haz-mat squad, etc. They actively search while patrolling NJT property, and while on the road between locations for LoJack hits, flagged vehicle registrations, wanted persons, narcotics, weapons, etc. They also have jurisdiction in the Pennsylvania cities of Morrisville and Philadelphia despite being a New Jersey agency, and are the only non State Police agency allowed to perform traffic stops on the NJ Turnpike Authority highways (NJTP & GSP).
Crazy huh?