U.S. Imprisonment Rate Reaches 20-year Low

The U.S. prison population now stands at its lowest in almost four decades for 2015, resulting in the lowest rate of incarceration in a generation, the Department of Justice announced Thursday.

Reuters reports the drop was driven by changes in federal and state corrections policies that include drug treatment programs and the sentencing of fewer nonviolent drug offenders to federal prisons.

Roughly one in 37 adults in the U.S. was under some form of correctional supervision at the end of last year, the lowest rate since 1994. The number of federal and state inmates at the end of last year was down by more than 35,000, or 2.3 percent, from 2014, making it the biggest drop since 1978, the year-end report released by the DOJ said.

At the end of 2015, 458 inmates had been sentenced to more that a year behind bars for every 100,000 American residents. That number was the lowest since 1997, when it was 444, according to the report.

Federal inmates represented forty percent of the decline in the U.S. prison population, whose numbers fell more than 7 percent to 196,500. 2015 marked the third straight year of declines.

The Justice Department’s early release of roughly 6,000 nonviolent drug offenders late last year accounted for much of the federal drop. President Obama’s shortening of the sentences of 1,176 federal inmates—including 153 last week—also contributed to the drop.

The number of inmates decreased by nearly 2 percent to 1.33 million in state prisons. From 2014 to 2015, 1.33 million people were incarcerated. Twenty-nine states also showed a drop in the number of their prisoners.

With last year’s drop, the number of state and federal inmates has declined about 6 percent since peaking in 2009, but is still well above 1978’s number, which was 300,000.