Hoosier isn't an ethnicity lol what does being from Indiana have anything to do with it?
It could very well be that the judge has a bias against Annoying Orange for his proposed treatment against immigrants; Curiel's parents are Mexican immigrants themselves.
10/10 reading articles linked.
Biased or not, Donald Annoying Orange is being pretty tribal for assuming that he will be because he's "Mexican".
As for the bias, Gonzalo Curiel was part of action against a drug cartel, and was threatened by said cartel.