So one or two major cases that redefine the nature of a legal system is not an issue of always or mostly happens. I bet you consider the Rodney King incident happenstance. Your comment is mainly conjecture as the statistics are not available to prove or disprove either point. A simple case as illustration. A black man has a higher chance of going to jail for a crime in the US than any other ethnic group.
As for honor killings I would again ask anybody to show me an incident where those committing the crime have stated that religion or culture was the reason for their actions. Hell I would even take a veiled reference at this stage.
And I am sorry Brits regularly ignore hooliganism and binge drinking as a national problem at a local level.