An activist has sued the agency for information about U.S. guns smuggled to Mexico and Central America, data that researchers say would provide insights into cross border firearms trafficking.

On October 20, a California federal judge heard arguments in a lawsuit seeking to compel the Bureau of Alcohol, Tobacco, Firearms and Explosives to turn over data about guns smuggled from the United States into Mexico and Central America. The data, if released, would represent just the second time in two decades that the ATF has offered a detailed glimpse inside its firearms tracing database, which has been a black box to the public since Congress restricted its disclosure in 2003.

Dr. Eugenio Weigend Vargas speaks with The Trace about what the data shows