[MikeD]

I am in SA as well, and I have a related question about school police. What is their jurisdiction? If it is only on campus, then why do the various ISD police have cars? I’ve never understood why we have so many overlapping levels of police in San Antonio. For those not from here, we have city police, county police, the constable, and ISD police.

[Straight Vermonter]

I’m in VT so things may be different in your location but all of our city cops and even university cops are state police officers. Smaller colleges do have security guards (not cops) who have very little authority and generally are not armed.

[Disambiguator]

I’ve never understood why we have so many overlapping levels of police in San Antonio

If you're ever in the ABQ area, be very careful in the vicinity of US 550 and NM 528. That area is prowled by six (count 'em) different agencies, to wit:
Bernalillo PD
Sandoval County Sheriffs
NM State Police
Rio Rancho PD
Santa Ana tribal police
Federal Police (BIA)