President Joe Biden praised the measure as “an important step toward reversing longstanding inequities”.
It’s a 180 for a legislator who, three decades ago, created a harsh crime policy that is today politically contentious.
However, it might help Mr. Biden, a Democrat, shore up dwindling popularity among younger voters in an election year.
Thursday’s proposal does not overtly legalize marijuana for recreational use, as is presently the case in 24 US states and the District of Columbia. Thirty-eight US states have also legalized marijuana for medical purposes.