The parole software was NOT being fed data for "will this person commit another crime". It was being fed data for, "will this person be a suspect for another crime".

The significant difference is that selective enforcement biases the data that it was trained on. Said selective enforcement has multiple causes, including the fact that heavier patrolling in black neighborhoods makes catching crimes more likely.

The size of the selective enforcement bias shows in a number of ways. For example consider drugs. In surveys, the usage of illegal drugs is the same in blacks and whites. And yet 6 times as many blacks are arrested for using illegal drugs as whites.