How long is too long behind bars?

Late last month, Sen. Rand Paul, R-Ky., told his colleagues that the nation’s mandatory minimum sentencing laws are ineffective. He’s leading a bipartisan coalition of senators who want Congress to reform the laws and give judges more sentencing leeway.

“Each case should be judged on its own merits,” Paul told The Washington Times. He’s pushing for the Federal Safety Valve Act, a bill that would allow judges to grant fewer years than the mandatory minimum sentence. The bill reflects the main sentiment driving sentencing reform: Judges should evaluate cases and offenders on a case-by-case basis.

“[J]udges, not legislators, are in the best position to evaluate individual cases and determine appropriate sentences,” said Sen. Patrick Leahy, D-Vt., one of the lawmakers backing the bill. But those who support minimum sentencing worry that anything less will allow for too much leniency.

Mandatory minimum sentencing laws have been a part of the American legal system for centuries but gained real weight in the 1980s when Congress passed The Anti-Drug Abuse Act. The law made minor drug possession a serious criminal offense. For example, a first-time offender caught carrying 5 grams of crack cocaine—worth a few hundred dollars—would face at least five years in prison.

Lawmakers hoped minimum sentencing would help law enforcement agents and judges “crack down” on drug dealers and ultimately get drugs off the street. But critics say it’s only responsible for overcrowding prisons, wasting millions of tax dollars, and disproportionately fracturing minority communities. Although surveys indicate the majority of crack cocaine users are white, 80 percent of those arrested, charged, and convicted for possessing the drug are African-American.

The laws also lead to an exponential increase in the number of those incarcerated. Currently, 2.2 million Americans sit behind bars—716 per 100,000—the highest percentage of the population of any industrialized nation. Meanwhile, according to the 2010 U.S. Census, states annually spend between $12,000 and $60,000 on prison inmates, but only between $9,000 and $18,000 on students.

Rand’s Safety Valve Act would allow judges to sentence offenders to less than the minimum time if they meet certain requirements. The goal is to encourage judges to reserve minimum sentences only for the most dangerous criminals, saving money along the way.

Supporters of minimum sentencing say they help keep crime rates down and could be used to fight other crimes, like child pornography. “Congress now has only one available tool to make sure that sentences are not too lenient and do not reflect unwarranted disparity,” Sen. Chuck Grassley, R-Iowa, said.

But the push for reform is gaining ground. Two days after Paul’s testimony before the Senate, Attorney General Eric Holder announced his own planned reforms. Federal prosecutors, he said, will no longer seek mandatory minimum sentences for nonviolent, low-level offenders. Instead, they’ll direct them to community service and drug treatments programs: “By reserving the most severe penalties for serious, high-level or violent drug traffickers, we can better promote public safety, deterrence and rehabilitation, while making our expenditures smarter and more productive.”