Why does it always have to be one and not the other?
Also you assumption is wild. Heres why? Blacks are harassed and confronted by police more often, with more frequency, charged with minor crimes more often, accused of assault more and prison sentences are typically longer or more harsh than their white counterparts.
Knowing AND defending those facts allows you to then turn around and claim "Hey, they're MUST be in prison for a reason"
As long as the unequal treatment and unfair harassment isnt considered the only "reason" left is they're just bad.
We saw the report from Fergueson...Theres another report in California that shows the same thing. You saw the racist emails passed around the departments.
And your conclusion is: Blacks are a large part of prison SO they must be a large part of crime