That's a question many have asked after suspects in several horrific mass shootings were found only later to have left social media hints of violence that went unheeded for years. Now a New York lawmaker has introduced a bill that would require police to scrutinize the social media and online searches of handgun license applicants, and disqualify those who publish violent or hate-filled posts.
"We certainly want to make sure we're putting weapons in the hands of the right people and keeping them out of the hands of the wrong people," said state Sen. Kevin Parker, a Brooklyn Democrat who added he was inspired to act after the Pittsburgh synagogue shooting suspect left social media rants that Jews were "children of Satan."
Free-speech watchdogs and even some gun-control advocates have already raised concerns about the bill, which would require handgun applicants to turn over login information to allow investigators to look at three years' worth of Facebook, Snapchat, Twitter and Instagram posts. Google, Yahoo and Bing searches over the previous year also would be checked.
Licenses could be denied if investigators uncover threats of violence or terrorism or the use of racial or ethnic slurs.
Parker's bill comes as people are increasingly wary about their online lives being tracked.
But social postings are commonly checked by everyone from human resource workers to police officers. A survey of more than 550 police departments several years ago by the International Association of Chiefs of Police found more than half use social media for listening or monitoring and three-quarters of them use it for intelligence.
While the prospects of Parker's bill passing are uncertain, he has already succeeded at one of his goals of creating "fodder for discussion," including pushback.
Tom King, president of New York State Rifle and Pistol Association, the state's NRA affiliate, said the bill would be the beginning of "the slippery slope of taking away your First Amendment" free speech rights.
At the American Tactical Systems gun range, a short drive from New York's Capitol, gun owners called the proposal unnecessary and intrusive.
"I don't think the government should have access to anybody's history, especially for pistol permits," Steve Wohlleber, who works at the range. "And the state police have enough to worry about besides checking everyone's social media."
David Pucino, a staff attorney at the Giffords Law Center to Prevent Gun Violence, said that while he shared the legislator's goals, he thought there were better alternatives, such as another bill that would create a court order of protection to bar people considered dangerous from possessing or buying guns.
Civil rights attorney Norman Siegel said he believes bill language directing police to consider "commonly known profane slurs or biased language" is too broad to pass constitutional muster.
"A person could be prejudiced," Siegel said. "That doesn't mean he's not entitled to his Second Amendment right."
On a practical level, the measure would mean more work for police in New York who already check the criminal and mental health histories of handgun license applicants.
Albany County Sheriff Craig Apple, whose department processes a few hundred applications every year, said "it's definitely going to bog things down a bit" in a licensing process that already can take from 120 days to a year to complete.
Parker countered that states have the authority to limit hand gun use for public safety.
"If you're afraid of your personal privacy," he said. "Don't apply for a handgun license."