Paul Armentano is deputy director of the National Organization for the Reform of Marijuana Laws (NORML).

The D.C. Council is considering a bill to fully legalize marijuana and regulate the retail marijuana market. The council decriminalized minor marijuana possession in 2014 ; later that year, voters approved an initiative that removed penalties for the private adult possession and personal cultivation of cannabis. Some might opine that these decriminalization policies are enough. But for lawmakers to truly address the ills of cannabis prohibition, legalization is necessary.

Why is legalization and regulation preferable to decriminalization? To answer this question, one first has to understand these two policy options and how they differ from one another. The concept of decriminalization as an alternative public policy option for low-level marijuana offenders is not novel. Forty-seven years ago, President Richard M. Nixon’s handpicked National Commission on Marihuana and Drug Abuse — the only presidential commission to be explicitly tasked with examining marijuana policy and making legislative recommendations — endorsed a policy of full decriminalization on a national level.

In the ensuing years, more than two dozen state legislatures — including Connecticut, Maryland, Mississippi, Nebraska, New York and Ohio — have enacted either partial or full decriminalization schemes into law. Many states — such as California, Colorado, Maine, Massachusetts, Nevada and Oregon — at one time imposed decriminalization but have since moved to legalize and regulate the plant entirely.

Though decriminalization is arguably superior to blanket prohibition, it perpetuates social ills associated with cannabis criminalization.

Specifically, decriminalization does nothing to reduce the size of the illicit cannabis market, nor does it bring any needed controls to this market. Under decriminalization, marijuana production and distribution remain dominated by criminal entrepreneurs rather than by licensed businesses. These underground transactions are unregulated and untaxed.

Legalization provides opportunities for lawmakers and local regulators to impose guidelines and controls regarding every facet of the marijuana market. Marijuana production and sales are restricted to state-licensed participants. Retail access is limited to licensed locations, and regulators may control location, business hours, signage, security, testing and labeling of cannabis products. Rules may govern the potency, serving size and appearance of specific marijuana products. Further, retail production and sales are tracked to reduce incidences of product diversion, and they are taxed accordingly, providing new streams of revenue.

Another shortcoming of decriminalization is that it perpetuates unnecessary interactions between consumers and members of law enforcement. Under decriminalization, the cannabis plant remains classified as illegal contraband. Police-citizen interactions remain costly to taxpayers and can sometimes result in tragic consequences.

Decriminalization also fails to right the wrongs associated with racially discriminatory policing. Nowhere is this result more evident than in New York City, where for decades police made end-runs around the state’s 1977 decriminalization law to continue to arrest hundreds of thousands of low-level marijuana offenders, more than 80 percent of whom were African American or Latino. By contrast, legalization is associated with dramatic and sustained declines in total marijuana arrests. For example, low-level marijuana court filings in Washington declined 98 percent following legalization. In Oregon, total marijuana-related arrests fell 96 percent. In Colorado, marijuana possession arrests declined by 88 percent.

But what about the concern that legalization will foster a predatory commercial cannabis industry, much like Big Tobacco in the 1980s? Ideally, these concerns can be addressed by the enactment of common-sense regulatory policies, combined with the promotion of evidence-based public-service campaigns discouraging misuse and abuse. In the case of tobacco, such policies have succeeded in driving down cigarette use, young people’s especially, to historic lows. These results were not achieved by banning cigarettes altogether or by arresting adult tobacco users, but by better regulating the market and by better educating would-be consumers. Many of these tried-and-true principles can be applied to the legal cannabis market.

In short, a pragmatic regulatory framework that allows for the legal, licensed commercial production and retail sale of marijuana to adults but restricts and discourages its use among young people, coupled with a legal environment that fosters open, honest dialogue between parents and children about cannabis’s potential harms, best reduces the risks associated with the plant’s use or misuse. By contrast, advocating for marijuana’s continued criminalization under the law, or maintaining its status as an illicit commodity under a scheme of partial decriminalization, results in perpetuating and compounding many of the adverse social consequences associated with the failed policy of prohibition.

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