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Criminal Justice Reform - Mass Incarceration

The United States faces two distinct but interconnected challenges: violence and mass incarceration. Ensuring safety is an urgent and essential responsibility of a society and is a core dimension of delivering on the promise of justice. The United States has been remiss in attempts to fulfill that responsibility because of an over reliance on incarceration as the primary pathway to ensuring safety. Substantially reducing violence will require acknowledging the limitations of prisons as a strategy to deliver safety or justice. And ending mass incarceration in America will require taking on the question of violence. 

The national prison population began a gradual descent after 2009, lessening by nearly 113,000 (6%) from 2009 through 2016. Several factors contributed to this decline: ongoing decreases in crime rates leading to fewer felony convictions; scaling back “war on drugs” policies; increased interest in evidence-based approaches to sentencing and reentry; and growing concerns about the fiscal cost of corrections and its impact on other state priorities. The state of California alone was responsible for 36% of the overall population decline, a function of a 2011 U.S. Supreme Court ruling declaring its overcrowded prison system to be unconstitutional and subsequent legislative responses to reduce the use of state incarceration.

Despite the decline, the overall pace of change is quite modest. A recent analysis documents that at the rate of change from 2009 to 2016 it will take 75 years to reduce the prison population by half. And while 42 states have experienced declines from their peak prison populations, 20 of these declines are less than 5%, while 8 states are still experiencing rising populations.

To aid policymakers and criminal justice officials in achieving substantial prison population reductions, this report examines the experience of five states – Connecticut, Michigan, Mississippi, Rhode Island, and South Carolina – that have achieved prison population reductions of 14-25%. This produced a cumulative total of 23,646 fewer people in prison with no adverse effects on public safety. (While a handful of other states have also experienced significant population reductions - including California, New York, and New Jersey – these have been examined in other publications, and so are not addressed here.

The five states highlighted in this report are geographically and politically diverse and have all enacted a range of shifts in policy and practice to produce these outcomes. All five were engaged in the Justice Reinvestment Initiative process, spearheaded by the Pew Charitable Trusts and the Council on State Governments, which was designed to work with stakeholders to respond to the driving forces of prison expansion in each state and to develop strategies for change in policy and practice.


This publication highlights California’s successful efforts to build public higher education access for thousands of incarcerated and formerly incarcerated students, both in custody and on college campuses throughout the state.

"Nearly 40 percent of the U.S. prison population — 576,000 people — are behind bars with no compelling public safety reason, according to a new report from the Brennan Center for Justice at NYU School of Law. The first-of-its-kind analysis provides a blueprint for how the country can drastically cut its prison population while still keeping crime rates near historic lows."

Sections cover: the current prison population; time served in prison today; ending prison for lower-level crimes; reducing time served for other crimes; and recommendations and cost savings.

Cover image for How many Americans are Unnecessarily Incarcerated

A conversation with Jasmine Heiss from the Vera Institute of Justice about a recent poll that uncovers American's souring sentiment toward incarceration policy.

It's no secret that America has an incarceration problem. And being "tough on crime" is something politicians proclaim in election years to prove that they care about safety. But a recent poll commissioned by the Vera Institute of Justice shows that the tide is turning when it comes to what people want for their communities. A majority of Americans—67 percent overall, including 61 percent in rural areas—agreed that building more jails and prisons does not reduce crime.

While politicians make remarks about the dangers of "inner-city crime," incarceration rates in major cities have fallen while rural communities have seen the most growth in incarceration rates and the jail population. Across the nation, when those polled were asked what they wanted their communities to invest in to improve quality of life, building prisons and jails (35 percent) lagged far behind other measures like providing jobs and job training (92 percent), investing in schools and youth programs (87 percent), and investing in mental-health treatment centers (87 percent).

In fact, nearly half (49 percent) of respondents said they believed "too many people are in jail for the wrong reasons," and 55 percent agreed that the country's criminal justice system discriminates against poor people. CityLab spoke with Jasmine Heiss, a director of outreach and public affairs strategist at Vera, about what this new data means and how it might lead to changes in policy around incarceration.

This memorandum summarizes the results of a national survey of 2,000 American adults taken from February 27-March 5, 2018. This survey focused heavily on rural areas, where incarceration rates tend to be much higher than in the nation’s major urban areas. In order to build a robust sample of rural residents, this survey included 1,000 interviews in counties designated as rural. Sample for this survey came from three separate files from Target Smart corresponding to three lists of counties classified as “Rural”, “Small and Mid-sized Metros”, and “Large Metro” with 50 percent coming from the rural list and 25 percent each from the latter two. This sample was of the general population over 18 years of age with 50% of the records being for cell phones and 50% for landline phones. During processing, the sample was clustered according to race, age, gender, and region. 


"After decades of stability from the 1920s to the early 1970s, the rate of imprisonment in the United States more than quadrupled during the last four decades. The U.S. penal population of 2.2 million adults is by far the largest in the world. Just under one-quarter of the world's prisoners are held in American prisons. The U.S. rate of incarceration, with nearly 1 out of every 100 adults in prison or jail, is 5 to 10 times higher than the rates in Western Europe and other democracies. The U.S. prison population is largely drawn from the most disadvantaged part of the nation's population: mostly men under age 40, disproportionately minority, and poorly educated. Prisoners often carry additional deficits of drug and alcohol addictions, mental and physical illnesses, and lack of work preparation or experience. The growth of incarceration in the United States during four decades has prompted numerous critiques and a growing body of scientific knowledge about what prompted the rise and what its consequences have been for the people imprisoned, their families and communities, and for U.S. society. [The report] examines research and analysis of the dramatic rise of incarceration rates and its affects. This study makes the case that the United States has gone far past the point where the numbers of people in prison can be justified by social benefits and has reached a level where these high rates of incarceration themselves constitute a source of injustice and social harm."

Chapters following an executive summary are: introduction; rising incarceration rates; policies and practices contributing to high rates of incarceration; the underlying causes of rising incarceration—crime, politics, and social change; the crime prevention effects of incarceration; the experience of imprisonment; consequences for health and mental health; consequences for employment and earnings; consequences for families and children; consequences for communities; wider consequences for U.S. society; the prison in society—values and principles; findings, conclusions, and implications.

The Growth of Incarceration in the United States: Exploring Causes and Consequences Cover

The rise of mass incarceration, spanning the 1970s to the early 2000s, was characterized by continuous, unified growth in both prison and jail populations across states and counties. In contrast, the past decade has given rise to what is widely recognized as an era of reform, with prison admission rates declining by 24 percent since 2006 and jail admissions rates down 25 percent since 2008. The national declines, however, mask the new dynamics of mass incarceration.

The growth that characterized mass incarceration’s rise has fractured into four dynamics that vary from state to state and county to county. Contemporary decarceration exists alongside continuous growth, stagnation, and jurisdictional shifts between prisons and jails, akin to a shell game. This report provides a first-in-kind look at the state of incarceration by moving beyond the convention of using state prison populations, illuminating both where meaningful change has happened and where true reform has remained elusive.

The overall pace of decarceration has varied considerably across states, but has been modest overall. Thirty-nine states and the federal government had downsized their prisons by 2017. Five states—Alaska, New Jersey, Vermont, Connecticut, and New York—reduced their prison populations by over 30% since reaching their peak levels. But among the 39 states that reduced levels of imprisonment, 14 states downsized their prisons by less than 5%. Eleven states, led by Arkansas, had their highest ever prison populations in 2017.

By yearend 2017, 1.4 million people were imprisoned in the United States, a decline of 7% since the prison population reached its peak level in 2009. This follows a nearly 700% growth in the prison population between 1972 and 2009. 

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