If you watch a few body camera videos, you’ll see police using cell phones a lot to talk to superiors. Better quality, doesn’t use radio bandwidth, more private, probably not recorded for the public record.

The Cruise first responder procedure (https://drive.google.com/file/d/1qjR38RAQ2cgjxic69TMseT_-Bhj...) instructs them to call Cruise to take the vehicle out of AV mode, if needed.