New Analysis: State and Federal Prison Population Trends

Letters to Editors

From: The Sentencing Project

I’m writing to share a new analysis with you that reveals broad variation in nationwide incarceration trends.

This comparative analysis of recent changes in state and federal prison populations contextualizes the scale and timing of efforts to downsize prisons. Through customized measures for each jurisdiction – calculating declines since each jurisdiction’s peak year, and increases in other states since 2008 – we assess the full impact of recent policy changes. The analysis reveals:

  • While the total U.S. prison population declined by 2.4% since 2009, incarceration trends among the states have varied significantly. Two-thirds (34) of the states have experienced at least a modest decline, while one-third (16) have had continuing rises in imprisonment.
  • Nine states have produced double-digit declines during this period, led by New Jersey (29% since 1999), New York (27% since 1999), and California (22% since 2006). Sixteen states, and the federal government, have had less than a 5% decline since their peak years.
  • Among states with rising prison populations, five have experienced double-digit increases, led by Arkansas, with a 17% rise since 2008. While sharing in the national crime drop, these states have resisted the trend toward decarceration.

These findings reinforce the conclusion that just as mass incarceration has developed primarily as a result of changes in policy, not crime rates, it will require ongoing changes in both policy and practice to produce substantial population reductions.


Marc Mauer