The Unheralded End of Mass Incarceration

# What changed

For decades the dominant story about American criminal justice was mass incarceration: large increases in imprisonment driven by rising crime in the 1970s–1980s and more punitive policy responses. That story is changing. Crime measures—police reports, arrests, and victim surveys—have declined dramatically over roughly 30 years. The result: fewer arrests, fewer prison admissions, and a shrinking prison population.

# How big the decline is

The number of people incarcerated in state and federal prisons has fallen about 25% since its 2009 peak. Prison admission rates for people under 30 have already dropped by half. Juvenile arrests and detention have fallen even further. A temporary homicide spike in 2020 did not reverse the long-term trend: homicides and many other categories of violent and property crime have since fallen, with one report noting city homicide rates are now at levels not seen in over a century.

# Who benefits

Black Americans have seen substantial declines in incarceration and victimization. The incarceration rate for Black Americans is already less than half what it was at the start of the 21st century, and that rate is projected to fall further, increasing opportunities for work, family formation, and community life that past generations saw as unlikely.

# Why this isn't headline news

The decline challenges common political narratives on both sides. Those who attribute criminality to immutable traits struggle to explain falling crime as the nation approaches majority-minority demographics. Those who describe the carceral state as permanently oppressive have to account for nearly two decades of falling imprisonment. The result: a major change in public safety has received relatively little sustained attention.

# The policy fork in the road

Officials now face two clear choices as fewer people commit crimes that lead to incarceration:

• Right-size correctional systems: close or repurpose facilities, reduce staffing and operating costs, and scale supervision to match lower levels of crime and admissions.
• Seek new ways to fill beds: expand pretrial detention, increase supervision revocations, or other forms of net widening that keep people in the system despite lower crime.

Evidence cited by the authors warns that net widening can increase harms without improving public safety, and that some juvenile facilities already have so few youths that staffing can exceed the number confined.

# Practical implications for policymakers and communities

# Bottom line

Mass incarceration as it existed is ending because fewer people—especially young people—are committing crimes that lead to prison. The next several years will test whether policymakers adjust systems to that reality or allow bureaucratic and financial forces to preserve prison-scale operations that impose ongoing costs on individuals and communities.