[benchaney]

There is a much more fundamental problem, which is that people are bad at understanding the difference between "is" and "should". No amount of information about what the world looks like tells you anything about what course of action is the most moral (and vice versa). If you are building a system that predicts recidivism rates (figuring out what "is"), then any piece of information that improves your accuracy is good. If you use that system to suggest sentences (making decisions about "should), then you are going to run in to a lot of problems.

[industriousthou]

I still don't understand why information should be elided from judges during sentencing. If public officials use data to worsen issues like recidivism rather than improve them, then those officials should be removed. If a judge can't be trusted to act responsibly and morally with accurate information about a defendant then why would we even begin to think that they're competent?

It's just the reality of how the justice system works. We have trust in the approximation of justice that the judiciary provides and constantly struggle to improve that judiciary.