Congressional Democratic leaders filed a marijuana legalization bill last week aimed at remedying the injustices of the drug war. But my experience as a regulator overseeing the implementation of Massachusetts’s effort to end marijuana prohibition tells me that without stronger measures, their plans will fall short of that worthy goal. In every state that has attempted to equitably legalize cannabis, big corporations quickly took over the market while those who were arrested and imprisoned under prohibition got next to nothing. We need to reverse this outcome at the federal level. But as federal lawmakers grapple with the complexities of beginning to repair the harms of the unjust war on drugs, it is critical that they study the experiences of states that have already attempted this.