The new year brings with it a new era for marijuana in California. January 1, 2018, marks the beginning of a new approach for Californians when adults can legally buy marijuana at a licensed retailer. The state regulates marijuana and marijuana products, the cultivation of marijuana accords with environmental and labor regulations and standards, and the state begins collecting tax revenue to fund community investment, environmental restoration, and drug treatment and prevention.

This is when the harms of marijuana criminalization begin to come to an end. It is a moment to celebrate, even as we recognize the challenges that lay ahead of us. For decades, Californians have suffered the consequences of marijuana criminalization. Despite having the largest medical marijuana economy in the world, California had no state system to regulate and control marijuana. No rules. No safeguards. No protections for consumers, workers, youth, or the environment.

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Under criminalization, the state arrested and incarcerated hundreds of thousands of people. Over 450,000 people were arrested for marijuana offenses in California in the last decade alone. And, not surprisingly, race played a key role in who got arrested.

Despite similar rates of use, police arrest African-Americans for marijuana possession at higher rates than whites in every state, and nearly every city and county, in the US California was no exception. In 2015 in black people in California were more than twice as likely as white people to be arrested for a marijuana misdemeanor and nearly five times more likely than white people to be arrested for a marijuana felony. Latinx people were 35 percent more likely to be arrested for a marijuana offense than white people.

The damage caused by these arrests was magnified and compounded by way of collateral consequences that can include revocation or loss of professional licenses, barriers to employment, barring from public housing, loss of educational aid, driver’s license suspension, bars on adoption, exclusion from jury service, loss of health care and other military benefits, and deportation.

Under criminalization, the environment was ravaged. Hilltops were leveled, forests and native vegetation cleared, streams destroyed and polluted, wildlife poisoned and killed, public land turned into dumping grounds for trash, pesticides, and fertilizers. Workers lacked even the most basic, minimal protection for stolen wages or injury on the job. Marijuana consumers and medical marijuana patients were denied access to a safe and regulated product and to information about what they purchased and consumed.

Marijuana prohibition in California was a colossal failure. In November of 2016, California voters opted for a new approach. Prop. 64 legalized the possession and personal use of marijuana for adults age 21 and older, and created a system to license and regulate businesses to cultivate, manufacture, distribute, test, and sell marijuana and marijuana products.

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In addition to tackling regulation, Proposition 64 was a sentencing reform measure. Proposition 64 reduced most felony and misdemeanor penalties for marijuana offenses and made those changes retroactive so that people can get their sentences reduced and old convictions taken off their records. The sentencing reform pieces of Prop. 64 took effect immediately. As a result, people were released from jails and thousands of people have had felonies and misdemeanors removed from their records. And there are thousands and thousands more people who can still benefit from these reforms and have their records changed.

State and local governments have been working on the licensing and regulation for the past year. This past summer, the legislature passed and the governor signed the Medicinal and Adult Use Cannabis Regulation and Safety Act to combine the medical and adult use laws and rules into one comprehensive regulatory system under the authority of the Bureau of Cannabis Control and a number of state agencies. Those agencies released emergency regulations at the end of last month and are poised to begin issuing licenses in the new year. After some uncertainty about the timeline, it appears that there will licensed business in California selling to adult consumers and patients on January 1.

Certainly, the shift to legalization will be slow and will not be without difficulty and the need for adjustment and improvement. All businesses must also comply with local licensing and rules. California has 58 counties and 482 incorporated cities across the state, each with the option to create its own rules or to ban marijuana businesses altogether.

There will be better access in some places than others. Some localities will take longer and will try different approaches. There are still a number of open questions on the state level that will be worked out in permanent regulations and future legislation. But the Governor, the Legislature, the state regulators, and (at least some) localities are working in good faith to make it happen.

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The biggest challenge moving forward is to ensure that in creating and implementing this new approach to marijuana in California, this new era, that we do not repeat the worst, most harmful aspects of criminalization. We have to be intentional about not allowing racism and discrimination to plague the enforcement of the marijuana offenses and fines that remain in place, such as citations for public consumption. We have to ensure that black and brown children are not suspended or expelled from school while their white counterparts are afforded access to newly funded treatment and prevention services.

We must look carefully at the new industry we have created to make sure that the people and communities that bore the brunt of criminalization are not excluded from opportunity and inclusion due to prior arrests or convictions, or due to a lack of access to banking, capital, or property. Some localities—Oakland, San Francisco, and Los Angeles—are creating local licensing schemes that center equity and inclusion. Others must follow their lead. This is our opportunity for a new, much better approach. We need to ensure that we seize it.