“Even if these sources of data bias could be identified and corrected, however, there may still be some group-based differences that are not attributable to data bias. If so, groups may experience different risk scores and categories that would not necessarily indicate bias. Further, it is often difficult (or impossible) to discern whether some observed group-level differences in data are genuine or reflect some sort of systemic bias.“
Yes (agreed)— justice in the US is supposed to happen at an individual level, so even if it were true that systemic bias made one more likely to be convicted of a crime (just for illustration say living in a high conviction zip code where 99% of people have been convicted of a crime) it would not be appropriate to use that data to predict or assess any individual human’s potential behavior.