WASHINGTON, May 24 (Reuters) - Errors by the U.S. agency that oversees the federal prison system resulted in 152 inmates staying in prison beyond their scheduled release dates between 2009 and 2014, a government watchdog said on Tuesday.
The errors caused three inmates to serve more than one year of extra time, and cost the U.S. government at least $1 million to incarcerate the prisoners for the additional time and to settle lawsuits by four of the late-released inmates, according to U.S. Justice Department Inspector General Michael Horowitz.
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Most of the late-released inmates served a month or less of extra time. Five federal inmates were also released earlier than they should have been during the same period, the audit found.
U.S. prison populations have soared in recent decades as a result of harsher federal and state-level sentencing policies. A recent White House economic study found that overcrowded prisons strain the U.S. economy more than they boost it or reduce crime.
One inmate in the audit report published Tuesday spent more than a year of extra time in prison because federal prison officials had not checked his online court records and therefore missed a judge's order substantially shortening his sentence.
While the 152 prisoners released late due to staff error were a tiny portion of the 462,000 federal inmates released between 2009 and 2014, Horowitz also identified more than 4,000 federal prisoners whose releases the Bureau of Prisons classifies as "untimely," but not due to staff error.
"Neither the Department nor the BOP has attempted to work with the other agencies to examine these cases, and they don't appear to fully understand all of the actions that can contribute to untimely releases," Horowitz said in a video accompanying the report.
The "vast majority" of untimely releases are the result of court-initiated actions and are not errors of any type, according to U.S. Justice Department spokesman Patrick Rodenbush.
"That being said, the Department of Justice is already taking affirmative steps to implement the recommendations of the Office of the Inspector General to further reduce instances of inappropriate untimely releases occurring," he said in an emailed statement.
Horowitz's report recommended seven ways for the Justice Department to better prevent prisoners being released at the wrong time, and asked the agency to show evidence of improvement by the end of August.