While some of those may be "inconvenient truths", punishment based on race is, strictly speaking, illegal in the US. Proxies for race (such as where they live) aren't much better.

Another part of the problem is the historical over-policing of minorities (particularly blacks and hispanics) in the US and the lower economic class. It's easy to view them as more likely to be recidivists until you realize that the neighborhoods they're going back to have more than normal police presence and they're more likely to be picked up for "nuisance" crimes like jaywalking, public drunkenness, and loitering. This will skew the numbers substantially in these sorts of models when the police are (largely) not applying the same standards to white people or those from higher economic classes (or whose neighborhoods are less tolerant of such behavior so it's not seen as often to begin with).