I would say shocking part is the cockiness of the police. They are so secure in their jobs that they know that even if they kill someone on camera or rough up protected entities like journalists nothing would happen to them.
1) Institutional and culture view of policing, vs say other western countries that are more community policing based.
2) General brotherhood of law enforcement and protecting each other. There is a lack of holding each other accountable.
3) General protection afforded by law, either explicitly or implicitly via half hearted attempts at prosecution / investigation etc.
These combined gives law enforcement as an organization and individuals a sense of normalcy in what they do, and also feeling of invulnerability.
This doesn't apply to all police officers of course, and I actually believe the majority are law bidding and trying to do good in a tough environment. There are probably also a non trivial amount that gets into law enforcement to wield power over others. Law enforcement needs to be held to a higher standard, and because of the power they wield must be scrutinized much more closely.
I mean, they literally have a license to murder.