This is part of a response I've heard from law enforcement (family and friends' family), usually as soon as someone else concedes, just so that the conversation doesn't sound like a complete indictment, that "most officers are good". The officer then corrects with, "99% of people are good", and that the same is true of police. Boy, does that sound good! Everyone is good, and the police, being a very small subset of the normal population are actually "better" than the population at large. The conversation just went from "cops need more accountability and oversight (and to stop killing people)" to...
Phase Two. Now that cops are the potential victims of unfair persecution and popular media slander campaigns (they're all good except the really bad ones who get caught, but they weren't "real" cops anyway, remember?), here come the examples of other accountability measures civilians think are helping them but are actually harming them.
Those damned lapel cams. Officer discretion keeps nice kids out of jail and keeps the really bad people locked up. But with lapel cams, any defense attorney can go back through police footage from the same officer and see where they selectively enforced laws in similar situations, making prosecution of "dangerous thugs" harder than it needs to be. You wanting to know that police aren't being violent and aggressive puts you and your children in DANGER.
And it's not prosecutorial overreach or disproportionate sentencing or selective enforcement that are the problems here- it's the defense attorneys. Lapel cams remove cop control over who stays in (or out) of jail, and that's a problem.
It's a really friendly and passionate argument, but it's rotten at its core. Police aren't judges, they don't know the law like attorneys, and they shouldn't be arbiters over the communities they serve. Does having sick laws designed to punish selected targets unduly built because selective enforcement is a fact make this a rats nest of an issue? Absolutely, and it makes attempts to address it a much more difficult and dangerous task for the public. What was BLM? If you watch TV, it was a movement of wanton destruction in response to the death of some criminals. What was it supposed to be? A campaign for recognition and reform of unfair sentencing, selective enforcement, and prosecutorial overreach through national awareness and grassroots activism. Don't worry if you didn't know; their local marches and sit-ins weren't exciting enough to be covered.