The road to hell is paved with good intentions. Your suggestion about the statistics would naturally start giving one group less jailtime for the same crime th

The road to hell is paved with good intentions. Your suggestion about the statistics would naturally start giving one group less jailtime for the same crime than other groups, and at some point the policy themselves would start affecting the statistics. It's the kind of thing that lends itself to groupthink and digs itself so deeply into people's minds that fixing the wrongs that would be created by this system becomes extremely difficult.