US Attorney General Eric Holder is calling for an end to mandatory minimum sentences for some drug-related crimes, as part of a larger initiative to streamline the criminal justice system. As the Associated Press reports, Holder will lay out the Justice Department's "Smart on Crime" initiative in a speech to the American Bar Association in San Francisco on Monday. Today's speech comes after the Justice Department launched a review of the criminal system earlier this year, as part of an effort to address the nation's severely overcrowded prisons.

Under Holder's proposals, people convicted of low-level drug offenses would not face mandatory prison sentences, and would instead be eligible for drug treatment or community service programs. Mandatory minimum sentences were introduced in the 1980s, as part of then-President Ronald Reagan's efforts to accelerate the "war on drugs" that Richard Nixon spearheaded in the early 1970s. The rules have come under intense criticism from legal experts and civil rights advocates in recent years, with many arguing that they disproportionately target minorities and put extra strain on the country's already-bloated federal prisons. According to the latest statistics from the Federal Bureau of Prisons, 47 percent of inmates are currently imprisoned for drug-related crimes — far higher than any other category.

"We need to ensure that incarceration is used to punish, deter and rehabilitate."

"We need to ensure that incarceration is used to punish, deter and rehabilitate — not merely to convict, warehouse and forget," Holder will say today. According to the attorney general, his proposals would make it easier for judges to delineate between non-violent offenders and those with ties to larger cartels, crime organizations, or gangs. Without the minimum sentencing, Holder argues, low-level offenders will face sentences that are "better suited to their individual conduct, rather than excessive prison terms more appropriate for violent criminals or drug kingpins."

Several state and local governments have already begun shifting resources to drug rehabilitation and treatment programs, though Holder says this approach should be adopted at the national level, as well. According to a 2012 report from the Government Accountability Office (GAO), inmate population levels swelled to nearly 40 percent above capacity in 2011, and are expected to reach as high as 45 percent above prison limits by 2018.

The Obama administration has taken steps to ease sentencing restrictions for some drug-related offenses. In 2010, the president signed the Fair Sentencing Act into law, lowering the discrepancy between minimum sentences for crack- and powder cocaine-related crimes. Previously, minimum sentences were much higher for crack-related crimes, disproportionately affecting African-American offenders.

"we cannot prosecute or incarcerate our way to becoming a safer nation."

Holder's proposal would also allow for some elderly, non-violent offenders to be released from prison, though the attorney general says his initiative would not weaken the ability of prosecutors to aggressively enforce federal law. But with federal prisons quickly approaching a tipping point, Holder says it's now clear that "we cannot simply prosecute or incarcerate our way to becoming a safer nation."

"Today, a vicious cycle of poverty, criminality, and incarceration traps too many Americans and weakens too many communities," Holder said. "However, many aspects of our criminal justice system may actually exacerbate this problem, rather than alleviate it."