US Law Enforcement Response, Time, Scale and Coordination (Galveston, TX)

[AlexanderHowl]

~20 minutes is probably a good response time for most urban police unless the local police were already on alert. If the victims are high profile or other police, or if the incident is in a downtown area, you can probably halve the response time. If the police are on alert for a potential atrack, you could halve the response time again.

Closing an connection to an interstate road is a completely different story. That usually requires permission from the governor of a state, as it could potentially be interfering with interstate commerce. At the best of times, you are probably talking an hour (local and state roads can be done with a call to the mayor/county comissioner, probably ~15 minutes). A blockade is a different story, as that assumes a temporary interruption of travel, and could be a reaction to a pursuit in progress).