Sen. Bernie Sanders released a proposal Thursday to legalize marijuana across the country and expunge criminal convictions related to the drug, embracing an overhaul of federal laws on the eve of a presidential forum expected to renew the debate on race, drugs and police violence.

Sanders becomes the latest Democratic White House aspirant to issue a plan for more tolerant drug laws, a shift from past presidential elections when Democrats, like Republicans, often promoted more toughness. Changing attitudes toward drug crimes, and a growing number of states legalizing cannabis, have ushered in a primary where ideas once seen as provocative have become mainstream.

Sanders’s plan, which aims to overhaul an approach he argues has unfairly hurtminorities, calls for using executive power to reclassify marijuana as a dangerous controlled substance and passing legislation to permanently legalize the drug. It would direct federal and state authorities to review, vacate and expunge past marijuana convictions.

“We’re going to legalize marijuana and end the horrifically destructive war on drugs,” the Vermont independent said in a written statement. “It has disproportionately targeted people of color and ruined the lives of millions of Americans.”

In his 2016 campaign, Sanders struggled to persuade African American voters to support him, and many instead gravitated to Hillary Clinton. He has taken steps in his second run to improve his standing, but so far there is little indication his outreach has made a significant impact in states with large minority populations.

Sanders released his marijuana plan a day before the start of the Second Step Presidential Justice Forum at Benedict College, a historically black institution in Columbia, S.C. South Carolina is an important early nominating state where African Americans are expected to account for a majority of Democratic primary voters. Sanders and eight other Democrats are scheduled to speak at the forum over the next three days.

President Trump is also slated to appear, taking the stage on Friday. He will participate in a symposium called “The Conservative Case for Criminal Justice Reform,” according to the 20/20 Bipartisan Justice Center, which is sponsoring the event.

Trump has presented himself as a champion of criminal justice reform, and in December he signed the “First Step Act,” a bipartisan prison reform law. The “second step” in the forum’s title refers to a push to move beyond that law.

While criminal justice reform is important to many black voters, African American leaders have condemned the president’s sometimes racist rhetoric, and it is not clear what kind of reception he will receive Friday.

Most recent polls show Sanders, who recently resumed his campaign activities after taking time off to recuperate from a heart attack, in third place behind Sen. Elizabeth Warren (D-Mass.) and former vice president Joe Biden. His two top rivals have also proposed sweeping changes to the nation’s marijuana laws.

Biden’s proposal is less far-reaching than those of Sanders and Warren. His plan, which he rolled out in July, would decriminalize marijuana use and expunge prior convictions for it. Biden’s plan advocates legalizing marijuana for medical purposes but would leave decisions on recreational use largely up to the states.

Biden would reclassify cannabis as a Schedule II drug, rather than Schedule I, so researchers would be allowed to study it.

Warren, like Sanders, supports legalizing marijuana and erasing past convictions.

Eleven states and the District of Columbia have legalized marijuana use to some degree, and many more allow it for medicinal purposes. Increasingly, prominent Democrats, along with some Republicans, have become outspoken advocates of relaxing criminal penalties for using the drug.

Former House speaker John A. Boehner (R-Ohio), for example, joined the board of a cannabis company last year and favors legalization.

But some divides have remained. In the early days of the Trump presidency, his administration signaled an intent to crack down on marijuana under then-Attorney General Jeff Sessions. More recently, Trump said he would leave it to states to decide whether to legalize the drug.

“We’re going to see what’s going on,” Trump said in late August when asked whether the federal government would legalize marijuana during his presidency. “It’s a very big subject. And right now we’re allowing states to make that decision. And a lot of states are making that decision.”

Trump administration officials have raised alarms about marijuana use among pregnant women and young people. In August, Surgeon General Jerome M. Adams and Health and Human Services Secretary Alex Azar said the drug “carries more risk than ever.”

The marijuana industry, however, has become lucrative as more states have legalized it. Sanders, who is running on a platform of curtailing income inequality and reining in the power of big companies, says he would create provisions to prevent large corporations from dominating the market.

His plan would ban tobacco companies from participating in the industry, for example, and would offer resources for people to start cooperatives and nonprofits.

The Sanders plan would also use taxes on marijuana sales to help promote minority businesses. It would do away with regulations requiring drug tests to receive public benefits, prevent officials from removing residents of public housing for marijuana use, and prohibit products and labels that target young people.