I think the whole 'issue' of blacks being shot more often/ending more often in jail is purely because of the fact you cannot judge other races' expression as well as your own race. Generally whites are more dominant in most western countries, and thus expressions and actions are misinterpret, leading to more arrests and shootings of the other race(s). This is scientifically proven and is also the cause of less interracial relationships than there is possible for example. For example: You wouldn't be able to identify a black person being a white as easy as another white person. Think about how you feel like all asians look the same to you.
Also because black culture is generally more aggressive and often relies on 'being' stronger/more dominant than another person causes a lot of problems, rather than being submissive when you need to be (in case of a officer for example).
Ofcourse there are probably some racist events other than this, but it generally is not the most dominant cause other than simple culture difference.
About the statement itself: I don't really care, every group has the right to come up for themselves, whether it be black, feminists, or political views, etc etc. It's not a 'all lives matter or you're racist' thing imo.