Firearms Trafficking: U.S. Efforts to Combat Firearms Trafficking to Mexico Have Improved, But Some Collaboration Challenges Remain, Report to Congressional Requesters [open pdf - 5MB]
"Violent crimes committed by drug trafficking organizations in Mexico often involve firearms, and a 2009 GAO [Government Accountability Office] report found that many of these firearms originated in the United States. ATF [Bureau of Alcohol, Tobacco, Firearms and Explosives] and ICE [Immigration and Customs Enforcement] have sought to stem firearms trafficking from the United States to Mexico. GAO was asked to undertake a followup review to its 2009 report (GAO-09- 709) addressing these issues. This report examines, among other things, (1) the origin of firearms seized in Mexico that have been traced by ATF, (2) the extent to which collaboration among U.S. agencies combating firearms trafficking has improved, and (3) the extent to which the National Southwest Border Counternarcotics Strategy measures progress by U.S. agencies to stem firearms trafficking to Mexico. To address these objectives, GAO analyzed program information and firearms tracing data from 2009 to 2014, and met with U.S. and Mexican officials on both sides of the border."
Government Accountability Office: http://www.gao.gov/