You really shouldn't take liberals that seriously.
Liberalism is the greatest threat that the Western civilization is facing right now. It is a self destructive ideology in its current form. In fact it is actually not that much different from communism. Here are the reasons why:
1. Communism's main enemy were the wealthier people, businessmen, etc. which were being blamed for inequality in societies and poverty. Liberals also have their main enemy which practically are the native people of their countries(European-Americans). You can literally say that they hate themselves.
2. Communism had atheist policy and now you also have liberals telling you how bigoted Christianity is (meanwhile completely tolerating Islam at the same time despite the fact that it's more radical then Christianity). The only God and religion that liberals belive in nowadays is "tolerance" (which in the real world means that you can't criticize blacks, gays, muslims and other kind of minorities as well as saying that whites are evil racists)
Wait a minute did I just listed muslims and blacks/immigrants as a minority? Did you know that Islam is the worlds fastest growing religion (https://www.google.com/search?q=burzua&ie=utf-8&oe=utf-8#q=worls+fastest+growing+religion)? Did you know that by the year 2050 it is predicted that European-Americans will become the minority in the USA (https://www.google.com/search?q=burzua&ie=utf-8&oe=utf-8#q=americans+will+become+minority)? Did you also know that the most popular baby name in London is Muhammad? (https://www.google.com/search?q=burzua&ie=utf-8&oe=utf-8#q=most+pupular+baby+name+in+london)
All of this makes the liberals feel really good.
3. The main goal of Communism was to create a classless society, liberals are also actively working towards. With movements such as feminism, transgenderism and shit like that they are saying that gender is a social construct, that a person can choose whichever gender he/she wants to be, some also think that there are more then 2 genders. Does this not sound crazy? Another thing liberals are doing to achieve their "tolerant society free of hate" is destruction of Christianity as well as eradication of nationalism, national values etc. This erodes the individual's concept of belonging to any kind of group( gender, country, race, ect) and by going further down this path you have a world of people who don't have national identities, common moral and value systems. Basically they are destroying every single value that the Western civilization was built on.
I'm sure that there are more common traits that Liberalism shares with Communism but I believe I've listed enough of them, therefore I can surely say that Liberalism is Cultural Marxism. Also keep in mind that majority of liberals don't even have a clue where they're going and what they're doing (referring to what I've said) when they preach their ideas. They truly believe that they're fighting for the right cause without even realizing what is happening and what is going to happen next.
Also notice how liberals, who are proud of being tolerant, react to other opinions that are different then their own. You'll find nothing tolerant in that.
As for the riots itself, I can only say a few things. First of all, if you look a little bit closer to each of those sensational cases in which a white policeman kills a black man, it's very easy to tell that it wasn't only the policeman's fault. I'm not too much into this particular event of Freddie Grey, but in all other cases when blacks started rioting after a black man got killed it was more then obvious that it all could have been easily avoided if the black man would have just complied to the police officer. Instead, they tried to pull off some stupid shit. The police in those situations was just overreacting at worst. So this whole idea about massive racism and power abuse in police is just ridiculous.
On the other hand, these kind of riots and savagery by blacks also make me have some "controversial" thoughts about them.