Under the most recent plan, defendants would be scored based on their prior criminal history, age, and gender. Those found to be either high or low risk would be flagged for a further assessment of their risk for recidivism and need for treatment or support. For that second-level review, the commission proposed putting those individuals through whatever assessment is used by the county probation department. In Philadelphia, that’s particularly controversial, as the risk-assessment instrument used by the probation department is a complex “black box” algorithm, meaning that it’s unclear how it weighs various factors in assessing any given individual.