More than two thirds of guns recovered at Mexican crime scenes originate in the U.S. For decades, Mexico has struggled with staggering levels of gun violence fuelled in large part by weapons trafficked across its northern border.

Now an investigation published by The Conversation has arrived at a new estimate of the scale of this illicit gun trade between the U.S. and Mexico in 2022: 135,000 guns.

Investigative journalist Sean Campbell and Topher McDougal, a professor of economic development at the University of San Diego, spent a year combing through multiple databases and court documents and conducting interviews to understand how the flow of guns works.

Their investigation reveals where in the U.S. the guns are coming from, what impact these American guns are having in Mexico, and how difficult it is for American law enforcement agencies to prosecute those trafficking guns across the border.

This episode of The Conversation Weekly was written and produced by Mend Mariwany and Gemma Ware. Mixing and sound design by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.

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