mass shooting都发生在禁枪区不是一个无可争议的事实,是来自John R. Lott的bad research,被NRA炒热了。
suffers from enormous flaws, including incorrect statistical modeling and dubious data-selection methodology.
http://www.thetrace.org/2015/06/gun-rights-advocates-say-that-places-that-ban-guns-attract-mass-shooters-the-data-says-theyre-wrong/