Principles of Risk Assessment
Risk assessment — measuring an individual’s potential for offending — has long been an important aspect of criminal justice, especially in connection with sentencing, pretrial detention and police decision-making. To aid in the risk assessment inquiry, a number of states have recently begun relying on statistically-derived algorithms called “risk assessment instruments” (RAIs). RAIs are generally thought to be more accurate than the type of seat-of-the-pants risk assessment in which judges, parole boards and police officers have traditionally engaged. But RAIs bring with them their own set of controversies. In recognition of these concerns, this brief paper proposes three principles — the fit principle, the validity principle, and the fairness principle — that should govern risk assessment in criminal cases. After providing examples of RAIs, it elaborates on how the principles would affect their use in sentencing and policing. While space constraints preclude an analysis of pretrial detention, the discussion should make evident how the principles would work in that setting as well.