After four decades of soaring prison growth and stubbornly high recidivism rates, the United States is rethinking its heavy reliance on incarceration. This shift has been led by the states, which recognize that the fiscal and human costs of widespread imprisonment have largely outweighed the benefits.

In many states, leaders are embracing a fresh correctional approach guided by data and anchored in evidence about what works to change criminal behavior. Tough-on-crime rhetoric has been increasingly eclipsed by smart-on-crime calls for a more enlightened criminal justice system that delivers better public safety at a lower cost.

The Justice Reinvestment Initiative (JRI) is a response to these impulses and a strong catalyst of state reforms. The justice reinvestment model aims to use data-driven policies and practices to reduce corrections populations and reinvest subsequent savings in proven public safety strategies. JRI, a public-private partnership between the Bureau of Justice Assistance and The Pew Charitable Trusts, was formally launched in 2010 to fund, coordinate, and help state and local justice reinvestment efforts.

Through JRI, 24 states have made legislative and administrative changes to their sentencing, release, and supervision policies, all in an effort to cut recidivism, control rising prison populations, and rein in costs. To evaluate their performance, state stakeholders and JRI partners have tracked system-level trends on key outcomes, monitored policy-specific data trends, and studied the impact of certain reforms.

Many of the states are early in the JRI process, so attempts to decipher impacts and draw firm conclusions are somewhat premature. That said, a review of state efforts shows that prison populations in more than half the JRI states were below previously projected levels in 2015. Put another way, JRI strategies enabled 15 states to either decrease their prison population or keep it below levels predicted before reform. On the fiscal front, JRI states reported $1.1 billion in savings or averted costs through 2016, attributable to reforms, and invested nearly half that ($450 million) in crime reduction strategies.

These and other outcomes described in this report are promising. Also heartening is a culture shift that is increasingly placing data and evidence at the core of modern correctional practice. Still, challenges remain.

Some states have hit multiple barriers limiting their ability to pass reform legislation or fully translate reforms into practice on the ground. These obstacles must be addressed to ensure JRI’s potential is not squandered. In addition, ongoing vigilance is critical to document successful strategies and sound the alarm when reforms veer off track.