I blame a lot of it on the "equality of outcome" hiring practices. If they hired like they used to decades ago: big, strong, confident guys that could think on their feet, we would have less issues. Lots of them now have small-man (or woman) syndrome or are scared of physical alterations so they go overboard when they feel like they have to use force. Having said that I know some cops and it's a tough job. Work in shit long enough and you're bound to get some on you.