I tried to search for the original source to see if I could find how they are calculating theses costs but didn’t have any luck.

I mention this because NYPD budget is often referenced as $6 billion, but that’s only operating costs, and the actual amount is closer to $11 billion (including fringe benefits like overtime and funding the NYPD pension).

With a 2020 GPD of $20,936 billion Then 0.8% of that is $167 billion

If we assume that policing costs are more closely tied to population rather than GDP we’d expect that NYPD costs to be about 2.5% of national amount. That’s approximately $4.2 billion.

But NYPD costs are $11 billion, which is 6.5% of estimated national policing costs (for 2.5% of the population).

Admittedly, I can imagine that there are reasons why a big city area might have higher than average costs, but 6.5% makes me feel that the 0.8% of GDP might be either underestimating how much US spends as part of GDP, or calculating national costs using different methods for different countries.

A huge problem is the massive, and influential, police union. Police resisting change at an individual or local level is one thing, but their union is a huge coordinated lobby that works against anything that would be better for the public if they perceive it as even slightly unfavorable to police.