The dramatic increase in the average amount of time served by federal inmates cost taxpayers an estimated $2.7 billion in 2012 and is largely the result of policy choices made by federal lawmakers during the 1980s and 1990s. During that period, Congress created the U.S. Sentencing Commission, which established guidelines that increased sentence lengths; abolished federal parole, requiring inmates to serve a much larger proportion of their sentences behind bars; and enacted mandatory minimum sentences for a broad variety of offenses, requiring judges to impose penalties set out in statute.
These policies were crafted in response to rising violent and property crime rates and growing concerns about public safety. The best available research, however, indicates that longer prison terms have little or no effect on recidivism and crime rates, and that recent sentence reductions for certain federal offenders have had no measurable impact on public safety.