This report was published April 2009 by the national non-profit educational organization Violence Policy Center.
From the report's executive summary:
This report, based on indictments and criminal information filed in U.S. district courts in thesouthwest United States, conclusively refutes the gun lobby’s claims. The information containedin these government documents clearly demonstrates?by the make, model, caliber,manufacturer, and retail source of firearms seized in criminal trafficking cases?that themilitary-style semiautomatic firearms easily available on the U.S. civilian gun market are asignificant component of the weapons being trafficked to, and utilized by, the Mexican cartels.
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