Katie Park Graphics by

In 2017, the U.S. prison population dropped below 1.5 million people for the first time since 2004, according to a new report by the nonprofit Vera Institute of Justice. A decline in several states with large prison populations, including Maryland, Louisiana and Illinois, is responsible, along with a drop in federal prisoners.

Maryland saw the largest drop, with 1,916 people exiting state custody, representing a 9.6 percent decrease, according to the report. Louisiana and Illinois, each with larger populations, lost 1,943, or 5.4 percent, and 2,230, or 5.1 percent, respectively. Although the prison population in each state has been declining for several years, between 2016 and 2017, Maryland and Louisiana experienced the largest single year decreases in their prison populations in a decade.

Researchers credit sentencing and other criminal justice reforms that have passed in each of the states in recent years for the decline. Yet, despite the declines in Louisiana and Maryland, some lawmakers are pushing to scale back some of the law changes, citing rising violent crime rates.

States with largest percent decrease in prison population from 2016-2017

Maryland -9.6% since 2016 -22.9% since 2007 Connecticut -7.5% since 2016 -33.9% since 2007 Rhode Island -7.5% since 2016 -28.5% since 2007 Louisiana -5.4% since 2016 -10.1% since 2007 Illinois -5.1% since 2016 -8.4% since 2007

In 2016, Maryland Gov. Larry Hogan, a Republican, signed the Justice Reinvestment Act into law, calling it “the largest and most comprehensive criminal justice reform to pass in Maryland in a generation." The bill reduced sentences for some low-level drug crimes, eliminated mandatory minimum sentences and improved parole and probation policies.

News Inside The print magazine that brings our journalism behind bars.

The new legislation was the result of several years of research and advocacy led by Pew Charitable Trust and the Bureau of Justice Assistance. In 2006, BJA and Pew launched the Justice Reinvestment Initiative to help states reduce their swelling prison populations. Since 2007, 34 states have adopted new legislation developed through the initiatives.

Louisiana also signed on. In 2017, Louisiana Gov. John Bell Edwards, a Democrat, signed into law a series of bills that some have been hailed as the most comprehensive reforms in the state’s history. For years Louisiana has had the highest incarceration rate in the country. With the new legislation, which reduces penalties for repeat offenders, offers more alternatives to incarceration, and reduces maximum penalties for drug crimes, the state is poised to shed its long held title. Some of the effects of the legislation were felt almost immediately when nearly 2,000 inmates were released from prison in November due to a change in the way the state calculated prisoner’s good time.

In 2015, Illinois Gov. Bruce Rauner signed an executive order creating a commission on criminal justice and sentencing reform. The commission was tasked with understanding the main drivers of incarceration in the state and proposing reforms to reduce the population by 25 percent by 2025. At the start of 2017, Rauner signed several measures to achieve his goal, including eliminating mandatory minimums for some crimes.

The report’s authors hope the timely snapshot of the country’s prison population—gathered from state corrections websites and interviews—can help continue to move the needle on criminal justice reforms. The federal Bureau of Justice Statistics releases official data on state and federal prisoners every year, which includes detailed demographic information, but the 2017 data won’t be available until the end of 2018.

“There is a lot of talk about reform in states where the prison population is still growing,” said Jacob Kang-Brown, one of the report's authors. “For these states it is important to know that many places that are seeing success aren’t driving up the crime rates.”

In several states, the prison population increased between 2016 and 2017.

States with largest percent increase in prison population from 2016-2017

Tennessee +6.6% since 2016 +14.4% since 2007 Utah +4.9% since 2016 -0.3% since 2007 Kentucky +3.7% since 2016 +6.3% since 2007 South Dakota +3.6% since 2016 +19.9% since 2007 Wyoming +3.2% since 2016 +17.6% since 2007

While 30 states reduced their numbers, in 20 states the prison population increased between 2016 and 2017. Tennessee topped the list with a 6.6 percent increase, or more than 1,000 prisoners. Kentucky rose by 3.7 percent, or slightly more than 800 prisoners.

Data show that the majority of prisoners in Maryland and Louisiana are incarcerated for non-violent crimes. But a recent spike in the violent crime rate in each state has sparked an interest in revisiting some of the landmark legislation. In 2017, Maryland had 343 homicides, a record-setting number. And in April 2018, lawmakers passed a sweeping crime bill to address the violence.

Critics of the bill argue it threatens to undermine some of the progress made by the previous legislation in reducing mass incarceration. Moreover, they argue, the legislation was hastily put together and not data-informed.

“There is a feeling that something has to be done,” said Keith Wallington, state based strategist at Justice Policy Institute. “No one can ignore the fact that there is an increase in violent crime, but they never could identify what to do.”

In Louisiana, lawmakers are debating a set of bills that could roll back some of the 2017 legislation. Some prosecutors argue that newly released inmates have left prison only to commit new crimes, and that reduced sentences weaken prosecutors ability to encourage drug users to go to treatment or comply with the terms of their probation.

Pete Adams, executive director of Louisiana’s District Attorney Association, doesn’t see the new bills as a rolling back of last year’s legislation. Instead, he says, the focus should be on spending the money saved on locking people up on programs that help inmates participate productively once released.

“This will not have a long term reduction in incarceration rates if we don’t spend the resources required to provide rehabilitation, education, and mental health treatment to help turn people around,” Adams said. “If we let people out without any support, we are gonna see them again, and when they come back they come in for a longer period of time.”

Correction: An earlier version of this story misattributed a quote to Oliver Hinds, the report's lead author. The quote, taken during a phone interview with several people present, came from Jacob Kang-Brown, another author of the report.