All those jobs were dumped on cops, who aren't that good at it.
Especially dealing with crazies and druggies, and having no good place to send them.
On the other hand, cops are too hard to fire. It's not like they're stack-ranked. The bottom few percent are not fired for underperforming. Bad cops are a minority, but they're not ex-cops soon enough.
And over represented on street duty because the specialty task force jobs, management and investigator roles are where the high achievers work their way to.