In the US, local policing is controlled and implemented at the city/county level. So in homogeneous and/or rural/small town communities the police tend to be reflective and respectful of the culture and identity of the population they serve, but this also means you can see some pretty wide variances in terms of the competency, cronyism, and corruption in police forces depending on the locality. These forces might receive funding from the feds to buy certain equipment or cooperate on investigations, but they operate essentially independent from the federal and even state governments, the president can't just ring them up and tell them to do this or that. Contrast this relationship with the big cities, where most cops tend to live in the suburbs and further out. In these places, you have cops, who tend to be conservative minded, enforcing the laws in leftist areas that hate the optics of police arresting their beloved minorities. So there are very different dynamics and relationships playing out in terms of how people interpret police (in the US anyhow). There are some cops that indeed relish the idea of exerting their power on the populace, whether it be right or left wing authorities authorizing such tyranny, but there are many who I do believe truly want to help people and protect OUR rights. At least in the US, it really isn't as a simple as police good or bad.