I'd hate to see someone use this kind of bad logic when deciding who is a criminal.
Oh dear. I have bad news about cops.
A fascinating study from Stanford looked at police traffic stops nationally around the daylight savings switch (as a natural experimental control) and found pretty hard evidence cops treat black drivers very differently during the day (i.e. when they can see their skin color).
https://news.stanford.edu/stories/2020/05/veil-darkness-redu...
Additional aspect of this: "you're a white supremacist" is almost certainly a First Amendment protected statement of opinion that can't be defamatory.