Apparently, it was all legal.

Though an investigation continues, it appears that everything Stephen Paddock did last Sunday night, before breaking the windows in his 32nd-floor hotel room and pouring gunfire onto a crowd at a Las Vegas country music festival, complied with state and federal gun laws.

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Another study, released in June by researchers led by Stanford law Professor John Donohue, found that overall violent crime rose 13 to 15 percent more over a 10-year period in 33 states that allow their residents to carry concealed handguns, with few or no restrictions, compared with states like California that allow local law enforcement offices to deny requests for handgun permits.

Using data through 2014, Donohue found no evidence to support a 1997 study by two University of Chicago researchers that concluded “right-to-carry” laws reduced violent crime.