“Just say no.” “This is your brain. This is your brain on drugs.”

Having been a teenager during the Reagan/Bush years, those slogans are as familiar to me as “I want my MTV" and “Time to make the donuts.” During the 1980s, the “war on drugs” was as central to our political and social world as the Cold War. The harsh criminal laws enacted in the 1980s in response to increased drug use and violence was the norm for most of my lifetime. Sending thousands of young drug users to prison for long periods was embraced and viewed as a critical weapon in the battle raging on the streets.

We know better now, 25 years and decades of research later. We have learned that more time in prison is likely to result in outcomes that are worse, not better. Of the hundreds of thousands of people leaving prison each year, more than two-thirds are expected to be arrested within the first three years. We can improve these outcomes through programs based on effective interventions and sentencing policies based on evidence. The results? Enhanced public safety, fewer victims, and better use of limited resources.

Yesterday, Congress took a big step in the right direction by approving a bill that reduced the disparities between mandatory crack and powder cocaine sentences and eliminated the five-year mandatory minimum for first-time possession of crack. The Senate passed the bill earlier this year. This is monumental on many fronts. First, as a matter of fairness and justice, the crack-powder cocaine disparity was appalling: a person convicted of crack cocaine possession received the same mandatory prison term as someone with 100 times the amount of powder cocaine. Eighty percent of those convicted for crack cocaine are African American; whites are the main users of powder cocaine. Because of political compromise, the bill does not eliminate the disparity—it remains 18 to 1—but still, the reform is significant.

Second, according to the New York Times, this is the first time since the Nixon administration that Congress has repealed a mandatory minimum sentence. This is huge, even though many states—notably New York with its reform of the Rockefeller Drug Laws in 2009—have repealed mandatory minimums in recent years. Third, the bill received bipartisan support, was passed on a voice vote, and was cosponsored by Republican Jeff Sessions, a former U.S. Attorney from Alabama. Though the states have passed significant bipartisan criminal justice reform in recent years, it seems as if Congress is finally realizing that harsh sentences (posturing as “tough on crime”) may not be the best solution to these problems.

Fourth, a bill that repeals mandatory minimum sentences and increases the amount of drugs necessary to trigger a conviction will reduce the number of people sent to prison. Although many states saw a drop in their prison populations in 2009, the federal government did not—its numbers increased by 3.4 percent (6,838 people), to an all-time high of 208,118. Less incarceration translates into reduced spending; the Congressional Budget Office estimates that shorter sentences for those convicted of crack cocaine possession will save the federal prison system about $42 million over the next five years.

In the states as well as in the federal system, unfair and unjust sentencing laws still outnumber logical, evidence-based ones. Many of these laws result in a disproportionate number of people of color behind bars throughout the country. Still, the bill passed by Congress yesterday and making its way to President Obama’s desk is a significant step toward righting the wrongs legislators committed in the name of the war on drugs.