If you want to see evidence of this yourself, I'd recommend stopping by the 78th precinct. NYC's finest have many creative examples to offer.
Edit: A recent article on the phenomenon[1]. It's hard to get statistics for this kind of thing, since the NYPD has demonstrated a tactical indifference towards it.
[1]: https://hellgatenyc.com/ghost-car-license-plates-illegal-but...
Am I understanding you correctly that the police staff themselves use illegal or obscured plates on their private vehicles which they park at the police employees parking lot, with no consequences whatsoever? If so this is insane.
Yes[1].
> at the police employees parking lot
Nope, they park illegally on the sidewalk instead[2]. This includes on blocks with public schools[3].
> with no consequences whatsoever? If so this is insane.
Yes, and yes.
Edit: I forgot to mention: documenting any of this comes with a risk of fines or arrest[4]. You will also be ignored if you attempt to report it[5].
[1]: https://nyc.streetsblog.org/2023/02/01/are-police-disciplini...
[2]: https://www.bloomberg.com/news/articles/2023-04-12/mapping-t...
[3]: https://www.vice.com/en/article/3ak54k/how-one-brooklyn-neig...
[4]: https://hellgatenyc.com/nypd-try-to-illegally-park-then-tick...
[5]: https://nyc.streetsblog.org/2021/10/25/nypd-ignores-council-...
I’m not aware of a court case that has tried to fight this, probably in part because of procedural challenges (the NYPD spans 5 boroughs with 5 different court systems, standing is unclear, etc.). Unfortunately, the city’s courts probably just aren’t equipped to handle this kind of en masse, “mild” collective punishment by law enforcement itself.
(I live on one of the most heavily used SBS routes in Brooklyn, and I've been disheartened by the blatant disregard trucks and other large cars have for the bus lane and bus parking slots. The stop closely to me is more often than not occupied by a trailer truck, meaning that the SBS bus unloads 50+ directly into traffic.)