The cavalcade of 2020 presidential hopefuls pulling for marijuana legalization is getting larger. California senator Kamala Harris reinforced her sympathies with the weed community on Tuesday with the release of her new book The Truths We Hold: An American Journey. In it, she calls for regulation of cannabis, and more intensive research into the drug’s effects.

“Something else it’s past time we get done is dismantling the failed war on drugs—starting with marijuana,” writes Harris in an excerpt you can find on Google Books. Primary among the senator’s reasoning is the War on Drugs’ blatant racism. She cites the fact that at the beginning of 2018, 93 percent of all cannabis possession arrests made by the NYPD were of people of color.

“These racial disparities are staggering and unconscionable,” Harris says. “We need to legalize marijuana and regulate it.”

None of this is to say that Harris has come out as cannabis industry booster, per se. The candidate is careful to acknowledge that there is much we don’t know about the science of cannabis, particularly in relation to the way it affects our bodies.

But that lack of scientific evidence, she argues, is no reason to continue prohibition. Indeed, marijuana’s current federal classification as a Schedule I drug (having no accepted medical use) has brutally handicapped researchers hoping to conduct clinical studies on its effects.

“That means committing ourselves to doing the research, listening to what the science tells us, and acting on that information in our approach,” Harris concludes.

Like many of her peers, Harris’ thoughts on cannabis legalization have undergone a distinct evolution. In 2014, news cameras caught the then-attorney general laughing off the issue of legalizing cannabis in California, saying simply of the pro-legalization stance taken by her Republican challenger for her position, “He’s entitled to his opinion.” In May of last year, she officially reversed this seemingly credulous outlook, announcing her support for Senator Cory Booker’s Marijuana Justice Act.

Making marijuana legal at the federal level is the smart thing to do and it’s the right thing to do. Today, I’m announcing my support for @CoryBooker’s Marijuana Justice Act. pic.twitter.com/cOh3SjMaOW — Kamala Harris (@SenKamalaHarris) May 10, 2018

But the political winds have shifted. California did, in fact, legalize adult use cannabis–as have many states across the country. And now it is nearly anathema for Democratic leaders to take a jocular attitude towards the future of federal cannabis law.

Last week, Jay Inslee, the Washington State governor and potential 2020 White House candidate, announced his plans to pardon cannabis misdemeanors. Bernie Sanders is the co-sponsor for the Marijuana Justice Act, which would federally legalize cannabis; expunge all weed-related federal convictions; and tackle Drug War-related racial justice issues. Senator Elizabeth Warren has also been an outspoken proponent of Marijuana Justice Act legislation.

The pro-pot tactic is a shrewd move on the part of Trump’s 2020 opponents given that six in ten United States residents believe the plant should be legal. It is unlikely to distinguish them much from the current president, however. Even Trump has expressed that he is not likely to stand in the way of the passage of the Marijuana Justice Act. “I will probably end up supporting it,” he told reporters in June.