That’s the problem. They do. For some definition of “police”.
Anyway, can any defense attorney use this video to shred these troopers’ credibility in any case where they’re brought as a witness for the prosecution? “You were filmed on video in this previous case plotting how to falsify a police report. How can we trust that this time you didn’t plant evidence (without stupidly recording yourself?)”
That seems like a heaping helping of reasonable doubt right there.