The NYPD isn’t the only police force in the country.
Again, if you use the military analogy, here we have soldiers stuck in a demoralized unit with bad leaders, that results in a war crime. What should a private assigned to that unit do?
The last answer was the best: he should have quit the force and gone to a better one. Even bad organizations usually realize that forcing someone good to stay won’t work, because they won’t play ball. So they let them go.
Leadership problems are solved at the leadership level, not below. The NYPD stayed bad until Giuliani came along, not before.
Giuliani didn’t straighten out the NYPD.
If the problems caused by King George III in the colonies were to be solved at the “leadership level”, there would have been no War of Independence.