> Police/fire/ambulances are there for emergencies, their drivers have better training (theoretically) in safe driving, and the vehicles bring attention to themselves.

By this logic, it’s ok for a police officer to drive through the park’s green on his way to work, with no emergency.

I mean, having seen pissing matches between civic authorities and cops play out, that's what I'd expect at the end of the day.

I'd argue that:

* if the siren is off, then “the vehicles bring attention to themselves” doesn't apply.

* if the siren in on, then they're not violating the park's rules, but they are violating the rules of their emergency vehicle.

Except most jurisdictions have rules governing things like that.