President Barack Obama, commenting last week on George Zimmerman’s acquittal in Trayvon Martin’s death, remarked on “a history of racial disparities in the application of our criminal laws—everything from the death penalty to enforcement of our drug laws.” A few months earlier, Attorney General Eric Holder similarly lamented new government data suggesting that even today “Black male offenders” are sentenced to federal prison terms “nearly 20 percent longer than those imposed on White males convicted of similar crimes.” These statements reveal that our nation’s first African-American president and first African-American attorney general are aware of serious racial discrimination in the administration of our nation’s criminal laws. The question is what they plan to do about it?

Neither the president, nor his attorney general, has followed-up or suggested a fix for the problem. Yet with one signature, Obama could make a remarkable difference: He could use his constitutional powers to commute the sentences of thousands of disproportionately Black inmates serving excessive prison terms for crack cocaine offenses. Put bluntly, rather than dropping occasional comments about high-profile criminal-justice incidents with racial overtones, both the president and the attorney general should make a focused and sustained effort to redress longstanding criminal justice disparities.

The disparity between crack and powder cocaine sentencing has been the most notorious example of profound racial bias baked into our superficially neutral criminal laws. For decades, federal law punished crack cocaine offenses more severely than comparable crimes involving powder cocaine. As a result, strict federal sentencing laws enacted during the height of a perceived “crack epidemic” hammered those who dealt in even tiny amounts of crack with five- and 10-year mandatory minimum prison terms.

Today, roughly 30,000 federal inmates, representing approximately 15 percent of the entire federal prison population, are serving time for crack cocaine offenses. And more than 80 percent of those men and women are African-American.