U.S. Attorney General Eric Holder

WASHINGTON (AP) -- One in every 20 federal prisoners could be eligible for early release under a potential sentencing change for inmates convicted of crack cocaine offenses that will be voted on Thursday.

Congress passed a law last year substantially lowering recommended sentences for people convicted of crack cocaine crimes, ranging from possession to trafficking. The idea was to fix a longstanding disparity in punishments for crack and powder cocaine crimes, but the new, lower recommended sentences for crack offenders didn't automatically apply to people already in prison. Now it is up to the six-member U.S. Sentencing Commission to decide whether offenders locked up for crack offenses before the new law took effect should also benefit and get out earlier.

Up to 12,000 of the some 200,000 people incarcerated in federal prisons nationwide could be affected. A report by the commission estimates that the average sentence reduction would be approximately three years, though a judge would still have to approve any reduction.

"There is a tremendous amount of hope out there," said Mary Price, vice president of Families Against Mandatory Minimums, an advocacy group for prisoners and their relatives. "There is a potential that people could see their sentences reduced, for some quite dramatically."

At a meeting in early June, commissioners suggested they want to apply the lower recommended sentences to at least some past offenders, but it is unclear how many. Advocacy groups have asked for the widest possible application while a group of 15 Republican lawmakers from the House and Senate wrote a letter to the commission saying the Fair Sentencing Act passed by Congress last year was not intended to benefit any past offenders.

At a hearing in early June about the potential changes, U.S. Attorney General Eric Holder took the middle road. He expressed support for making the new, lower guideline sentences retroactive but suggested limits on who should be eligible. Holder said prisoners who used weapons during their crimes or who have significant criminal histories should not be eligible. If the commission adopts that view it could cut in half the number of prisoners who would stand to benefit from 12,000 to approximately 6,000.

Any decision about who should be eligible for a reduced sentence will have to be approved by four of the commission's six members, who include judges and former prosecutors. Once the commission votes, Congress has until the end of October to reject or modify the guidelines, though that is considered unlikely.

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