An investigation by El Universal found that between the years 2000 and 2012, the U.S. government had an arrangement with Mexico’s Sinaloa drug cartel that allowed the organization to smuggle billions of dollars of drugs while Sinaloa provided information on rival cartels.

Sinaloa, led by Joaquin “El Chapo” Guzman, supplies 80% of the drugs entering the Chicago area and has a presence in cities across the U.S.

There have long been allegations that Guzman, considered to be “the world’s most powerful drug trafficker,” coordinates with American authorities.

But the El Universal investigation is the first to publish court documents that include corroborating testimony from a DEA agent and a Justice Department official.

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