It’s not a TV trope. It is the fucking law. Cops get to violate the law, legally, and claim ignorance. Cool, so you’ve never met a cop that would stand around while kids are being murdered. Well, there’s a lot of them in Texas. You’ve never met a cop that wouldn’t uphold the constitution? Well there’s a shit load of them in LA. Just because of your anecdotal experience of such great wonderful police, doesn’t mean the entire institution isn’t rotten to the core.