Medical errors, for example, are estimated to cause as many as 250,000 deaths per year [1].
There are millions and millions of daily interactions between police and civilians every year. Sadly, there will be some mistakes, some of which will be caught on camera.
It's important to be aware that what the media can be random, and media coverage is not always correlated with how important or prevalent a problem is.
[1] Johns Hopkins: https://www.hopkinsmedicine.org/news/media/releases/study_su...
Ok, the EU has 445M citizens[1] which means, by your logic, there should statistically be 40% more police "mistakes" than the US. Except there isn't. It is radically lower[2] (1536 for the USA in 2019 vs 51 for the EU in 2018/19).
[1] https://europa.eu/european-union/about-eu/figures/living_en [2] https://en.wikipedia.org/wiki/List_of_killings_by_law_enforc...