https://www.nytimes.com/2024/01/16/nyregion/mathew-bianchi-n...
Fun facts... the insignia you put on your license or on your car also has a thing like a registration tab... The FOP says its "to show your ongoing support", everyone else with a room temperature IQ knows its "to show you're 'paid up' on your protection money for the year".
Oh, and some enterprising souls have created "counterfeit" FOP insignia and stickers and other regalia (or for those tabs), and sold them on eBay... only to have the weight of the police union's attorneys come down on them with cease and desists, etc.
Biggest gang, etc.
I do agree with what you're saying, though, but the issue to me is why that's even something that should show up when your plates are run, "Oh, you're a cop somewhere, or used to be".
I have a friend who's a union leader (as in actually runs a sizeable union) and, in the eyes of most people, a straight-up socialist. He convinced me public sector unions are a horrible idea precisely because of the above. I had known about the above, but I always had trouble squaring my support for the right to unionize with the problems with public sector unions. He basically gave me permission to call a spade a spade.
... but the police unions that represent approximately 70% of the nation's police have negotiated it into their CBAs that this register "cannot be used for hiring or promotional purposes".