Arturo Rocha (@arocha221) is a political scientist from the Mexico City-based Center for Research and Teaching in Economics (CIDE). 

MEXICO CITY — After 12 years of roaring violence that has left over a hundred thousand dead and more than 30,000 missing — not to mention countless human rights violations by the security forces — the Mexican government is finally taking steps to redefine its role in the failed war on drugs.

Sen. Olga Sánchez Cordero, who will become interior secretary of the new government, last week presented a bill to legalize and regulate cannabis, from seed to sale. In a Congress largely dominated by Morena — the left-leaning party headed by President-elect Andrés Manuel López Obrador, who will be sworn in on Dec. 1 — the bill is not expected to face major hurdles and will probably become law next year.

The bill not only opens the door to a commercial market, but it also allows cannabis clubs, medical use and individual cultivation — up to 480 grams, or slightly more than one pound per year. While consumption in public spaces is authorized, all advertising will be forbidden, as well as the commercialization of edibles.

The bill will be the culmination of a long and tormented road toward legalization. It provides an institutional and commercial framework. Mexico is now poised to become the third country to allow a fully legal market of cannabis, after Uruguay and Canada.

However, the implementation of the law will be very different and faces major hurdles. Uruguay and Canada are two safe countries that have experienced the deleterious effects of global prohibition only from the periphery. Mexico is the epicenter of the war on drugs. The homicide rate in Uruguay is 7.69 and is 1.68 in Canada for every 100,000 inhabitants, according to the World Bank. The latest figures in Mexico put ours at 25.

While farmers in Montevideo and Alberta can cultivate marijuana peacefully, farmers in Guerrero and other Mexican states will face retaliation from drug cartels. Mexico is facing the highest homicide rate since the war against narcos started. Our conflict has never been more violent. While Canada and Uruguay — as well as the 10 states in the United States that have legalized recreational marijuana — can be free to experiment, the gravity of Mexico’s circumstances forbids us to do so.

This is not to say that Mexico can’t learn from others. Colorado has seen a surge in tax revenue, while fears of rampant addiction and surging crime did not materialize. But the state has seen an increase in fatal crashes involving drivers with marijuana in their system. In Uruguay, the experience reveals one main conclusion: Since the state failed to provide enough marijuana, supply fell short, and the black market largely survived.

Mexico must study these cases closely. The challenge will be achieving a successful balance between security, rule of law, public health and respect for personal liberty. Mexico’s best bet is to embrace evidence and slowly implement the new legislation, understanding our very particular context. Congress needs to carefully calibrate nudges, in the form of taxation, to shape the pace at which the legal market will supersede the illegal one. For a market to flourish securely, THC taxes should be implemented, and protection for farmers guaranteed as well. We also need legislation to reverse past drug convictions and release current nonviolent offenders.

Mexican lawmakers need to understand the complex interaction of different goals that, at times, clash with one another. For instance, a highly regulated marijuana market that aims to deter consumption will let the black market persist. But an aggressive competitive industry will make marijuana very affordable, denting cartels’ profits, which in turn could increase crime.

The Mexican government has utterly failed to combat drug cartels. Ending the ban on marijuana could be a useful tool to reduce their clout. But careless implementation will turn this promising chance into a tragic episode. If the new government embraces evidence and sets aside politics, this could be a very important first step to achieve the historical transformation they were elected to deliver.

Read more: