Error of impunity
Errors of impunity is a term used in Brian Forst's book Errors of Justice and in Robert Bohm's introduction to a special edition of The Journal of Criminal Justice on miscarriages of justice. They are defined as lapses that result in criminals either remaining at large or receiving sanctions that are below a socially optimal level. If convicting an innocent person, called a miscarriage of justice, is a Type I error for falsely identifying culpability (a "false positive"), then an error of impunity would be a Type II error of failing to find a culpable person guilty (a "false negative").
Forst divides errors of impunity into two categories. The first category is made up of those that are like car accidents: the community may be able to do more to prevent them, but generally prefers to consider them beyond the reach of the criminal justice system to do so. About half of all felony victimizations in the U.S. are not reported to the police, and many of those that are reported are committed by skillful, elusive offenders. The second category is made up of those errors that are real, unambiguous, significant, and avoidable. Examples include failures of the police to follow up leads to capture dangerous offenders and inmate escapees.
Errors of impunity can be caused in much the same ways as miscarriages of justice can, including, without limitation, the following:
Forst argues that a variety of social costs are incurred as the number of culpable offenders set free increases: public safety and the quality of life are compromised, the credibility of deterrent effectiveness is lost, and citizens become increasingly inclined to perceive injustices to victims and alienation from the police and courts, if not from government generally. As a result, Forst argues, the integrity of the justice system becomes threatened both by the reality and perception of ineffectualness. These lapses can run through the entire justice system, from ineffective policing and prosecution to weak sentencing and corrections.
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