At least 17 states, most of them led by Republicans, introduced bills this year trying to make it easier to buy, own and carry weapons, providing guns to teachers and declaring themselves Second Amendment sanctuaries, according to a FiveThirtyEight analysis. This continues a trend of Republican legislatures and governors increasing access to guns.
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We don’t know much about the effects most of these specific laws will have, because longstanding roadblocks on gun-related research mean we don’t know a lot about what kinds of gun laws prevent shootings, especially mass shootings. More than 20 years of research has found that increased availability of guns is associated with higher rates of homicide, and a 2014 study in the Journal of Urban Health found that a repeal of Missouri’s permit requirement for handgun purchases contributed to a 25 percent increase in firearm homicide rates in the five years that followed.
Great article from FiveThirtyEight, like almost everything they post. Lots of fact driven, heavily referenced points. Their primary focus is to report on polling of all sorts, using all kinds of high end data sciencey techniques. I highly recommend their website to deep dive on various topics.
FYI: I have my masters in computer science with a focus on big data/AI/ML, so I've done a ton of work like this in the past few years and can vouch for the quality of their work.