Trope: Police have to keep bad guy talking on the phone long enough to trace them and find their location. Professional bad guys hang up right before it triangulates their coordinates.
Apparently, Hollywood’s been getting this inspiration from a pre-digital age when they use this trope in movies. See link for more info. It’s just funny that most of the “tracing the call” scenes I’ve seen are definitely after the 2000’s.
Another link: https://slate.com/news-and-politics/2002/10/how-hard-would-it-be-to-trace-the-sniper-s-phone-calls.html
A fun gif: https://i.gifer.com/9QtC.mp4
The truly political move from the legislator would be to let them storm the capital. If you kill them all, then that makes you look bad. You let them do it, and it makes Trump an insurrectionist.