Arindrajit Dube, UMass Amherst economics professor, is co-author of the paper, “Cross-border Spillover: U.S. Gun Laws and Violence in Mexico.” The authors find that the expiration of the federal assault weapons ban in 2004 coincides with an increase in gun-related crimes and homicides in Mexico bordering on Arizona and Texas. A similar increase didn’t happen near the California border, perhaps because California has tough state gun laws, the authors say. (The New Republic, 6/15/11)