Sen. Kamala Harris plans to introduce a bill Tuesday that would decriminalize marijuana at the federal level. The bill, called the Marijuana Opportunity Reinvestment and Expungement Act, also looks to undo harsh marijuana drug sentences and encourage minority-owned businesses within the marijuana industry.

Activists and multiple 2020 candidates view the criminalization of marijuana as a civil rights battle. According to an analysis by the American Civil Liberties Union, arrest records between 2001 and 2010 showed blacks are 3.73 times more likely than whites to be arrested for the drug.

Harris had previously been an opponent of marijuana legalization. In 2010, Harris -- then San Francisco's district attorney and a candidate for California attorney general -- publicly opposed Proposition 19, which would have legalized the recreational use of marijuana in the state.

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"Spending two decades in court rooms, Harris believes that drug selling harms communities," Harris' campaign manager, Brian Brokaw, told Capitol Weekly at the time. "Harris supports the legal use of medicinal marijuana but does not support anything beyond that."

Recreational marijuana would not be legalized in any state for another two years, until 2012, when Colorado and Washington approved recreational use of cannabis.

By 2015, when she was running for the U.S. Senate, her stance had changed. She told the San Francisco Chronicle that she had "no moral objection" to legalizing the recreational use of marijuana. Harris also told the paper that she saw the legalization of recreational marijuana in California as "an inevitability," but that lawmakers "really do have to work out the details" of what that would look like.

The bill would also require states to "re-sentence and expunge records of prior marijuana-based convictions," according to Harris' office. It would also prevent immigrants from being "subject to deportation or citizenship denial based solely on a marijuana infraction," and "prohibit the denial of any federal public benefit (including housing) on the basis of possession or use of marijuana."

The bill would also introduce a 5% tax on "marijuana and marijuana products" in order to support grant programs to assist "socially and economically disadvantaged individuals" in the industry, as well as "the individuals most adversely impacted by the War on Drugs."

The bill would also require "the Bureau of Labor Statistics to collect data on the demographics of the industry to ensure people of color and those who are economically disadvantaged are participating in the industry."

Harris had previously voiced her support for marijuana legalization during an interview with "The Breakfast Club," a popular syndicated radio show that has hosted several presidential candidates this year. During that interview, she also admitted to smoking marijuana in college.

"Listen, I think that it gives a lot of people joy," Harris said on the program, "and we need more joy in the world."

Harris is also a co-sponsor of Sen. Cory Brooker's Marijuana Justice Act of 2019, which also calls for the decriminalization of recreational marijuana and investments into the communities disproportionately impacted by the War on Drugs.