In the Buffalo shooting the gun was purchased legally and NY also has a Red Flag law on the books. Several of the more recent shootings the individuals were prohibited from owning firearms and had them taken away but family gave them back before they committed the shootings.
The Assault Weapon ban of the mid 90's did nothing to changed the amount or nature of mass shootings. No amount of limiting magazines, types of stocks, etc. is going to cut down on what is clearly a mental health issue. In fact most school shootings have been done by individuals under 21 years old. If one wants to propose limiting the ability to purchase till after that age, good luck as the Supreme Court has already shot that one down as infringement of the 2A.
A national "Red Flag" law is also never going to pass due to many venues for abuse (nor would I support such a bill). If states want to pass one, they are free to do so, but it will not lessen the frequency of these events.
Reason has a good article highlighitng some of the problems with the most common "solutions" mentioned here and elsewhere for these types of issues.
Despite their practical limitations, expanded background checks are highly popular (although not quite as popular as Schumer suggested). A 2021 Morning Consult poll found that 84 percent of voters, including 91 percent of Democrats and 77 percent of Republicans, agreed that background checks should be required for all gun sales.
Schumer thinks the popularity of expanded background checks shows they are a "common sense" response to mass shootings. But this would not be the first time that "common sense" was wrong. "It's one thing to say that, regardless of the facts, you should just do something," Sen. Mike Rounds (R–S.D.) observed. "The question is whether something you would do would actually make a difference."
Even when it comes to the much larger category of gun homicides, there is little evidence that broad background-check laws "actually make a difference." A 2019 study found that California's 1991 expansion of background checks "was not associated with a net change in the firearm homicide rate over the ensuing 10 years."
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In a 2017 column that The New York Times republished in response to the Uvalde massacre, Nicholas Kristof, who supports new restrictions on firearms (including expanded background checks), notes that "the 10-year ban on assault weapons accomplished little, partly because definitions were about cosmetic features like bayonet mounts (and partly because even before the ban, such guns were used in only 2 percent of crimes)." Mary McCord, executive director of the Institute for Constitutional Advocacy and Protection at Georgetown University Law Center, glides over those points in another Time opinion piece published today, conflating arbitrarily defined "assault weapons" with "semiautomatic weapons," a much broader category that encompasses most handguns and many rifles that would not be covered by the ban that Biden supports.
https://reason.com/2022/05/25/in-respon ... trol-laws/