The British Exit has opened up civil unrest and an increase in activities much resembling an increase in anarchy beliefs in the younger generation. It's not an elderly person ganging up on anyone. It's the young, less well to do, less educated by life experiences that are at the root and being fanned into flame by liberal rhetoric.
Yes, British concerns about immigrants were one of the main reasons behind Brexit. While said concerns were not necessarily based on xenophobia, it is difficult to deny that xenophobia did have a powerful presence in the Leave campaign. As a result, British xenophobes came to believe that they had popular support when Brexit happened, which emboldened them to say things and do things that would've once been unthinkable.
The "Brexit" dilemma has nothing to do with police brutality or rebellious crimes. It is an issue pertaining to the world wide economy, not necessarily with law enforcement or crime. The Brexit dilemma affects the United Kingdom on a much larger scale than the United States. If anything, Brexit may just affect us by internationally traded stocks.
Referendums like "Brexit" do not inspire racially motivated violence. It is absurd to think that a vote would be enough motivation for someone to attack another based on race, ethnicity or gender. What is more likely, is that the referendum serves as an excuse or justification for someone to commit violent acts.