Governance Civil Justice
September 18th, 2019 8 Minute Read Issue Brief by Rafael A. Mangual

Issues 2020: Mass Decarceration Will Increase Violent Crime

The Narrative

"[F]ar too many people are locked up unnecessarily. As a result, the United States has the highest incarceration rate in the world."[1]
— Pete Buttigieg


"More people [are] locked up for low-level offenses on marijuana than for all violent crimes in this country."[2]
— Elizabeth Warren


"To help end the era of mass incarceration … take action to legalize marijuana, further reform federal sentencing laws, end private prisons and the profiting off of people in prison, and push states to prioritize treatment and rehabilitation for drug offenses."[3]
— Statement on Criminal Justice Reform,



The size of America’s prison population is driven by the incarceration of violent felons. These felons are held mostly in state prisons, which account for nearly 90% of inmates nationwide. Most prisoners are serving time for violent or weapons offenses, and the vast majority of them—even those incarcerated for nonviolent drug and property offenses—will go on to re-offend, sometimes by committing serious or violent felonies.

Slashing the prison population to match levels in the Western European democracies would require releasing significant numbers of violent and chronic offenders serving time for crimes that most Americans agree should lead to prison. Reducing or eliminating sentences would diminish the incapacitation benefits of incarceration and, given the extremely high rates of recidivism, would expose society to large numbers of people likely to commit more crimes.

Key Findings

1. Most prisoners are serving short sentences for serious, violent crimes.

  • 60% of state prisoners are serving time for murder, rape, assault, robbery, or burglary—four times the number convicted only of drug offenses.
  • Despite the portion of prisoners in for serious and violent offenses, less than 15% of state felony convictions result in more than two years served in prison; even 20% of those imprisoned for murder, and nearly 60% of those imprisoned for rape or sexual assault, serve less than five years of their sentences.

2. Most prisoners will re-offend post-release.

  • 83% of released state prisoners are arrested for a new offense at least once after their initial release.
  • More than one-third of those convicted of violent felonies in large urban counties had an active criminal-justice status—that is, either on probation, parole, or out pending the disposition of a prior case—when they committed their offense.

On the Record

“Like most prisoners, the idea of mass decarceration will prove quite dangerous.” — Rafael A. Mangual, Fellow and Deputy Director of Legal Policy

Who Goes to Prison

America’s prisons are filled with violent felons, most of whom serve short sentences. Of the 1,489,400 prisoners in state and federal penitentiaries, 1,306,305 (88%) are held in the state system and 806,700 (54%) are serving time for violent or weapons-related offenses.[4]  While nearly half (47.3%) of federal prisoners are serving time primarily for a drug offense, drug offenders constitute less than 15% of state prisoners. More than four times as many state prisoners (60%) are serving time primarily for murder (14.2%), rape/sexual assault (12.8%), robbery (13.1%), aggravated/simple assault (10.5%), or burglary (9.4%).[5]  In all, fewer than one in five American prisoners are primarily incarcerated for a drug offense—and very few of them are in for mere possession: drug possessors account for just 3.5% of state prisoners and less than 1% of federal prisoners.[6]

The violent felons in prison represent only a subset of those convicted of felonies, and most will not remain in prison for long. The U.S. Department of Justice reports that, from 2003 to 2009, only 40% of state felony convictions resulted in a prison sentence.[7]  When a prison sentence is imposed, the median term served in state prison is only 16 months; nearly 40% of state prison inmates serve less than a year, and nearly two-thirds serve less than two years.[8]  All told, less than 15% of state felony convictions result in more than two years actually spent in prison. Even 20% of convicted murderers and almost 60% of those convicted of rape or sexual assault serve less than five years in prison.[9

The Implications of Matching Europe

The U.S. prison incarceration rate of 455 per 100,000 is much higher than European levels.[10]  But releasing everyone imprisoned for drug offenses, larceny and motor-vehicle theft, fraud, DUI, and other public order, property, and unspecified offenses would bring this rate down to only 289 per 100,000—more than twice the rate of the U.K., three times that of France, and four times those of Germany and Canada. Aligning the U.S. rate with any of these nations would require releasing about 75% (more than 1.1 million) of America’s prisoners.

To achieve Western European incarceration levels, the U.S. would have to release many chronic and violent offenders and significantly slow the rate of incarceration for such offenders.

Released Criminals Re-Offend

Two things are clear from the data on recidivism and violent crime: the vast majority of prisoners who get released will go on to re-offend at some point; and even during the fastest period of prison growth in America, more than one-third of those convicted of violent felonies had an active criminal-justice status when the offense was committed (i.e., they were on probation, parole, or out pending the disposition of a prior case).

The Bureau of Justice Statistics (BJS) conducted a longitudinal study of recidivism among released state prisoners, following a cohort of more than 400,000 across 30 states for nine years.[11]  It found that 83% were rearrested for a new offense at least once during the nine-year period.[12]  This figure is significantly higher than the recidivism rate found in some previous studies that used a three-year benchmark.[13]  As the results of the BJS study make clear, a three-year benchmark period is inadequate. Only 68% of the prisoners in the BJS study had been arrested within three years.[14]  Indeed, “six in 10 (60%) of the 1,994,000 arrests during the 9-year period occurred from years 4 through 9,” and 47% of those not arrested in the first three years were arrested at some point thereafter, according to the study.[15]  Even 43% of the prisoners over the age of 60 were rearrested at some point.[16

It is worth noting that most offenses go unreported, undetected, and unpunished. That a released prisoner was not arrested within three years of his release does not necessarily mean that he did not commit any crimes.

Advocates of decarceration want to reduce the jail population by eliminating cash bail and diverting people away from incarceration and into programs such as probation or home confinement. But unlike jail or prison, these programs do not incapacitate dangerous offenders. According to BJS, 37% of violent felons in large urban counties between 1990 to 2002 “had an active criminal justice status at the time of their offense.”[17]  In other words, more than a third of those ultimately convicted were already on probation, parole, or out pending the disposition of a prior case when they offended. Of the 118 murder suspects identified by police in Baltimore in 2017, nearly 36% were on parole or probation at the time of the offense.[18]

Diversion or release might seem like an attractive option for the 18% of inmates imprisoned for drug offenses, but it’s important to remember that they are often dangerous criminals. Of those 118 murder suspects in Baltimore, seven in 10 had a prior drug arrest. Among the 400,000 released state prisoners followed by BJS, more than 75% of those who were initially incarcerated for drug offenses were subsequently arrested for a non-drug crime; 34% were later arrested for a violent crime.[19


Much of America’s serious violent crime is perpetrated by repeat offenders who, in many cases, could have been (but were not) behind bars at the time of their offense. Large-scale decarceration promises to make the problem worse.


  1. See Buttigieg, The Douglass Plan: A Comprehensive Investment in the Empowerment of Black America (Section entitled “Criminal Justice Reform”)
  2. See Warren, Remarks at “We The People” Summit at 15:12 (delivered on June 13, 2018 in Washington, D.C.).
  3. See Criminal Justice Reform,
  4. See Bronson & Carson, Prisoners in 2017 at p. 3 & Tables 12-15, Bureau of Justice Statistics (April, 2019).
  5. Id. at table 12.
  6. Bronson & Carson, supra note 5, at tables 12 & 14.
  7. See Durose & Langan, Felony Sentences in State Courts, 2000, Bureau of Justice Statistics Bulletin (June, 2003); Durose & Langan, Felony Sentences in State Courts, 2002, Bureau of Justice Statistics Bulletin (December, 2004); Durose & Langan, Felony Sentences in State Courts, 2004, Bureau of Justice Statistics Bulletin (July, 2007); and Durose & Farole, Felony Sentences in State Courts, 2006, Bureau of Justice Statistics—Statistical Tables (December, 2009).
  8. See Kaeble, Time Served in State Prison, 2016 at table 2, Bureau of Justice Statistics Bulletin (November, 2018).
  9. Id.
  10. U.S. rate calculated from a 2017 prison population of 1,489,400 (see Prisoners in 2017 supra note 5) and July 2018 estimated U.S. population of 327,167,464 (see U.S. Census Bureau Quick Facts: United States). For incarceration rates of other nations referenced, see World Prison Brief: Europe and North America.
  11. Alper, et al., 2018 Update on Prisoner Recidivism: A 9-Year Follow-up Period (2005-2014), Bureau of Justice Statistics (May, 2018)
  12. Id.
  13. See, e.g., Council of State Governments (CSG) Justice Center, Reducing Recidivism: States Deliver Results (June, 2017); and Zgoba & Slaerno, A three-year recidivism analysis of state correctional releases, Criminal Justice Studies: A Critical Journal of Crime, Law and Society, Vol. 30, Issue 4 (2017).
  14. Alper, et al., supra note 11.
  15. Id.
  16. Id.
  17. See Reaves, Violent Felons in Large Urban Counties, Bureau of Justice Statistics Special Report (July, 2006).
  18. See Kevin Rector, 2017 Homicide Data Provide Insight Into Baltimore’s Gun Wars, Police Say, Baltimore Sun (January 3, 2018).
  19. Alper, et al., supra note 11, at table 6.



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