You've already seen it, but Linoge over at Walls Of The City has created a great graph showing population, firearms deaths, number of guns and the relationships of these numbers and guess what? When the law-abiding have them, more guns = less crime. --Criminals can always get and carry guns; restrictive firearms laws only hinder the law-abiding.
One thing I'd like to add to his graph is a histogram showing the year-by-year increase in states moving to shall-issue carry permits. I ran my own crude version and it shows rough correlation with changes in slope of the the death rate: with more legally-carried guns, the death rate slows. H'mm.
Introduction to Sim
5 months ago