A much-heralded and widely cited study of 171 countries over nearly a half century purports to show more guns mean more mass shootings, but critics say the report uses bad methodology in a way that rigs the results. The study by Adam Lankford, a criminal justice professor at the University of Alabama, was published in the journal Violence and Victims in January and has been cited by media outlets -- including The New Yorker, The Washington Post and Time magazine. But... (GunPolicy.org)