First of all, nobody is claiming that all Black/black people are innocent people, and nobody is saying that all White/white people are bad people. Okay. ( I haven't decided. yet how to capitalize when I'm referring to a group of people, but why the fuck do people like Derec care?
I will try to explain. If one is referring to a group as if they are an ethnicity, than I would say using a capital letter is probably best. If one is simply referring to the color of one's skin, there is no need to use a capital. But, imo, this is a very trivial matter. Sometimes I use a capital and sometimes I don't. I'm not and never will be a grammar or spelling Nazi because I think language and its usage are fluid. As long as I know what you're talking about, I could care less if you're spelling and grammar don't go by the book. See what I did there? People in the Northeast use the expression, "I could care less" instead of "I couldn't care less". We who are from the NY metro area know exactly what it means when someone says, I could care less. Okay? There are all sorts of expressions that don't meet the standard of the formal usage of English. So, don't get your panties in a wad if someone uses a capital to describe a group of people or not.
For that matter, nobody has black skin and nobody really has pure white skin. I'm beige. Okay. My husband is now considered a "person of color" because these days, people of Arabic descent are ofter referred to as people of color. Do I think all of this emphasis on skin color is insane? Yes. Yes I do. My husband used to consider himself white, but now we refer to him as "whitish", because we love humor. But, I digress.
It's nuts, but social construct or not, people who are considered black have had to deal with systemic racism. Even, highly educated professional black folks who have never committed a crime or looked out of place, have been harassed by the police. I've heard many of their stories. I've read about many of their experiences. It's a lot more common than some of you seem to think, but some of you are too closed minded to consider the possibility.
One of my Black friends says that she has never been harassed by the police. I'm happy for her, but that doesn't mean that a good number of other people with darker skin haven't bee the victims of systemic racism by law enforcement. How many times do we need to post the statistics regarding harassment by the police toward Black folks? They've been posted before. Look it up for yourself if you really care.
Again, all "Black Live Matter" means is that black lives matter just as much as white lives and they should be treated with the same respect and consideration that white people are usually treated. That doesn't mean that white people are never treated unfairly by law enforcement. It doesn't mean that all black folks treat all white folks fairly. Humans are humans. I have no doubt that if a different race or ethnicity held most of the power, they too would look down on those who are different looking or have different cultural practices, but there has been systemic racism in the fucking US since its inception. It's not as bad as it was, but it does seem that with a few steps forward, there is always a racist backlash by those who don't want to give up the power or privilege that their skin color gives them. We should all be treated equally under the law.
And, even if there is more crime committed by black folks, that in no way should mean that all black males should be suspected of being criminals. That is why policies like "stop and frisk" were wrong. If you don't see that, then you are obviously a racist. Most racists don't even realize they have racist tendencies. I've lived long enough to know that because I've had too many white friends and coworkers who have made racist remarks in front of me, and then when I point it out to them, they respond with something like, "I'm not a racist. I have a black friend".

That's not the most harmful type of racism, but it's still racism. But using your one black friend as a token doesn't excuse all of the assumptions you make about Black people as a group.
You don't think systemic racism is still alive and well, read some fucking books on the topic. You'll learn a lot.