It makes no sense that thousands people sentenced for possession of the older, more familiar and more expensive powdered cocaine were given far more lenient treatment than those sentenced to long prison terms for crack, the cheaper crystallized form of the drug. For more than 20 years, Americans have been witness to a particularly senseless kind of criminal justice regressiveness: Like a bottom-loaded tax, it takes a harder hit on those lower down the economic scale.

Congress, spooked by the spread of crack in the 1980s, established a five-year mandatory minimum sentence for first-time crack possession, and set prison terms for crack possession equivalent to 100 times the same amount of powder.

Sen. Dick Durbin, D-Ill., who voted for the 1986 bill, said when crack first appeared, "there was near panic in the halls of Congress … It scared us to death. We overreacted."

Add the fact that most of those convicted for powder cocaine have been white, while some 80 percent of those convicted for crack are black or Latino, and the law all but collapses under the weight of its own injustice.

Unfortunately, even bad laws don't just go away. Fortunately, Congress has decided to help the dismantling of this one along. By voice vote, the House on Wednesday approved a bill, already passed by the Senate in March, to reverse the most blatant inequities in the 1986 law.

The Congressional Budget Office estimates the bill will save $42 million over the next five years in reduced prison costs. That would be one good argument for changing the law. Twenty-four years of gross injustice would be a better one.

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