What is the crack-cocaine amendment to the Sentencing Guidelines and why is it important?

On November 1, 2007, the U.S. Sentencing Commission amended the guidelines for crack-cocaine offenses, lowering the penalties for most crack cocaine offenses in section 2D1.1 of the guidelines by two levels.

On December 11, 2007, the Commission voted to make the amended guidelines retroactive to cases sentenced before November 1, 2007, with an effective date of March 3, 2008.

Through an amendment effective May 1, 2008 (Amendment 715), the Commission further modified section §2D1.1, revising the way in which combined offense levels are determined in cases involving crack and other drugs. The amendment, which was also made retroactive, provides that 1 gram of cocaine base equals 20 kilograms of marijuana and provides for a two-level reduction in the combined offense level for polydrug cases unless certain exceptions apply.