I found this interesting:
>> The CCRB receives thousands of complaints every year, but it is only able to substantiate a tiny fraction of them. In 2018, the agency examined about 3,000 allegations of misuse of force. It substantiated 73.
>> Investigators are often not able to reach conclusions on cases, in significant part because they must rely on the NYPD to hand over evidence, such as footage from body-worn cameras. Often, the department doesn’t do so, despite a legal duty to cooperate with CCRB investigations.