US voters in four states—Michigan, North Dakota, Utah, and Missouri—will decide whether to approve some form of legal marijuana on Nov. 6. The effects of their choices will likely waft all the way down to Mexico.

The rapid spread of legal marijuana across the US is displacing pot smuggled into the country by Mexican drug cartels. While it’s impossible to calculate the full extent of the cartels’ US pot business, seizures of illegal marijuana shipments at the border suggest changes in states’ laws are hitting them hard.

Annual US Marijuana seizures at the border with Mexico are falling

The decline in marijuana seizures at the US-Mexico border started in 2014, the year that Colorado and Washington became the first states in the US to legalize the sale of recreational weed to adults. Nine other states, including California, the country’s most populous and wealthiest state, as well as DC, have since legalized recreational use, further eating away at cartels’ market share. Another 22 states allow the medical use of marijuana in varying degrees.

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These days, Mexican growers and dealers are even facing competition from American legal weed in their own backyard: some discerning consumers are ditching locally-grown varieties (Spanish) in favor of those cultivated in the US and smuggled into Mexico.

Voters in the four states with pot initiatives on the ballot in the Nov. 2018 elections could speed up those trends. In Michigan and North Dakota, voters will decide whether to legalize recreational marijuana, while those in Utah and Missouri will weigh in on medicinal use of the drug.

Switching to other drugs

Pot advocates in both Mexico and the US see the decrease in illegal marijuana trafficking as a plus, but it’s also forced cartels to shift their business into more dangerous drugs. Methamphetamine seizures, for example, have shot up since 2014.

Seizures of fentanyl, a powerful opioid, more than quadrupled to nearly 1,400 pounds confiscated at the border from fiscal year 2016 to 2017. With two months left to finish fiscal year 2018, the amount of seized fentanyl had already surpassed that level.

Americans are unlikely to legalize fentanyl or methamphetamine in the foreseeable future, which raises the question of what else could be done in the US to dampen demand of those drugs.

Original Article – Quartz