Saul Loeb / AFP - Getty Images file Attorney General Eric Holder speaks Aug. 1 at a farewell ceremony for FBI Director Robert Mueller.

WASHINGTON D.C. - Attorney General Eric Holder directed federal prosecutors on Monday to change the way they file charges for some drug crimes, to reduce the number of convictions for offenses that carry inflexible, mandatory minimum sentences.

The nation’s top law enforcement official called for a “fundamentally new approach” to enforcing drug laws in order to help alleviate prison overcrowding and reduce race-based disparities in drug prosecutions.

“It's clear - as we come together today - that too many Americans go to too many prisons for far too long, and for no truly good law enforcement reason. It's clear, at a basic level, that 20th-century criminal justice solutions are not adequate to overcome our 21st-century challenges,” Holder told the annual meeting of the American Bar Association’s House of Delegates in San Francisco. “And it is well past time to implement common sense changes that will foster safer communities from coast to coast.”

The new policy involves the prosecution of low-level, non-violent drug offenders who have no ties to gangs, cartels or other large-scale organizations. They will be charged with offenses that — like those for most crimes — specify a range of months or years, allowing judges to decide sentence length.

Holder has long argued that mandatory minimums are contributing to the fact that the number of inmates in federal prisons has increased by 800 percent since 1980, far faster than the growth of the U.S. population.

U.S. Attorney General Eric Holder announces that the Justice Department will modify mandatory prison sentences for low-level drug offenders, while speaking Monday to the American Bar Association.

Some Republicans, including Sens. Mike Lee of Utah and Rand Paul of Kentucky, have joined Democrats in calling for eliminating mandatory minimum sentences for low-level drug offenders.

In a statement, Paul hailed the change in posture announced by Holder.

“The administration's involvement in this bipartisan issue is a welcome development. Now the hard work begins to change the law to permanently address this injustice,” he said.

Holder argued the policy shift reflected a “pragmatic” approach that he and President Barack Obama is needed in its enforcement of drug laws. He said that the widespread incarceration that results from mandatory minimum sentencing cost the U.S. $80 billion in 2010 alone.

Holder also directed federal prosecutors to go after the most serious offenses and most dangerous criminals, leaving local and state prosecutors to handle more of the less serious crimes.

“This means that federal prosecutors cannot - and should not - bring every case or charge every defendant who stands accused of violating federal law,” he said. “Some issues are best handled at the state or local level.”

Such a move would partially reverse the trend of recent decades toward more federalization of criminal prosecutions and would shift dwindling federal resources toward the highest priorities. But local officials also face budget cuts of their own and may not welcome such a move.

Nonetheless, Holder said, “By targeting the most serious offenses, prosecuting the most dangerous criminals, directing assistance to crime hot spots, and pursuing new ways to promote public safety, deterrence, efficiency and fairness, we can become both smarter and tougher on crime.”

In his prepared remarks, Holder also urged prison officials to offer more frequent compassionate release for older, non-violent offenders with compelling circumstances. And he recommended more use of prison diversion programs, such as drug treatment or community service.

“My colleagues and I are taking steps to identify and share best practices for enhancing the use of diversion programs - such as drug treatment and community service initiatives - that can serve as effective alternatives to incarceration,” he said.

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