Are you putting the camera anywhere near the radar units output?
I don't know how powerful the microwaves of a cruiser are, but a fighter jet's radar is turned off before taxiing cuz it'll cook a turkey from 10 feet.

Could be related to the department's Computer Aided Dispatch system. It would be interesting to setup a portable spectrum analyzer and watch for packets of data and see if they relate to the RF interference on the camera.

Don't video cameras use a crystal to maintain accurate timecode? I bet whatever it is that's causing this is pinging that crystal. I wonder if I used a DTE tapeless drive if there would still be a problem because there would be no physical contact and alignment issues like with tape. But maybe there would be with timecode because it and the crystal are electronic. If a DTE drive is the fix, then I can get ALL of my cameras back on-line and forget about tape!