Pareto in Prison.

The Pareto principle is based on the concept that roughly 80% of outcomes are generated by 20% of inputs, efforts, or contributors within a group. Using a national sample of U.S. prison inmates, we examined various percentile rankings of self-reported institutional misconduct to determine how much disorder is created behind bars by the most prolific offenders. Findings revealed that, regardless of sex, the top 20% of inmates were responsible for approximately 90% of all rule violations and write-ups received. These general patterns remained similar even after adjusting infractions for time served in prison. Further analyses indicated that membership within these high-rate groups was often significantly predicted by those who were younger, black, had more extensive criminal histories, committed violent crimes, resided in state facilities, anticipated being released, used drugs prior to their arrest, were diagnosed with a personality disorder or ADHD, and exhibited worse negative affect. Some sex-specific effects were also observed. The disproportionate impact these chronic offenders have on the prison environment is detrimental to all individuals who live and work around them. Future research should investigate specific types of misconduct, distinct time intervals of incarceration, and facility effects such as management style, security levels, or offender composition.