Gunmen associated with the Sinaloa Cartel pose in front of a sign threatening the Los Zetas Cartel. http://en.wikipedia.org/wiki/Sinaloa_Cartel#mediaviewer/File:ElChapoGuzman-gunmen.jpeg Legalized marijuana might help cut down on drug dealing in the US, but cartels are now smuggling the high-quality weed into Mexico for illegal sale there, Steven Nelson of U.S. News reports.

DEA spokesman Lawrence Payne told U.S News that traffickers working in the U.S. are stealing marijuana that's much higher quality and more expensive than pot that isn't grown legally.

Marijuana legalization advocates have argued that legalizing the drug in the U.S. would stop the illegal flow of weed from Mexico into the U.S., but now it seems that the reverse is happening with the cartels still present in the States.

Since marijuana became legal in more than half of U.S. states, in many cases for medicinal use but in some cases for recreational use as well. Americans are buying more weed that's grown in the U.S., according to NPR. That, in turn, is driving down the price of weed grown in Mexico.

And because the legal weed grown here is of higher quality, cartels can charge more for it in Mexico.

A lot of the marijuana the cartels are smuggling into Mexico is coming out of Colorado, Payne told U.S. News.

Marijuana is big business in Mexico. One grower who works in the Sinaloa state in Mexico told NPR how the system works.

Cartels employ growers who take on significant risk to supply the drug to the traffickers, and if the price of weed in Mexico keeps dropping, the growers will abandon their crops and stop working for the cartels. So the cartels are looking for other sources of weed that they can sell for more money.

We were warned about this back in 2012. Studies predicted that Mexican drug cartels would take a hit if marijuana was legalized for recreational use in states in the U.S., and rather than absorb the revenue loss, cartels are looking for other ways to make money from pot.

Only four states have legalized marijuana for recreational use — Washington, Oregon, Colorado, and Alaska — but more than a dozen others have legalized the drug for medicinal use. Washington, D.C. also recently legalized recreational marijuana use.

So far, only Colorado and Washington state have marijuana stores that allow people aged 21 and over to purchase small quantities of the drug.