Except it will inevitably lead to discrimination and abuse as it always has in the past. How much of the US justice system is based on harassing poor communities using that kind of excuse? Even if one community is actually less likely to commit crimes than another, if you send 90% of your policing forces there, using the excuse they it is just the way they are and things don't change much, you will find 90% of your crimes there. Even if twice as many unresolved crimes are happening in the the other area.

I actually think it's good to be able to discriminate against people with bad character.

If you can know the character of individual people, you have less reason to discriminate against those from statistically higher criminal communities.