People are wondering how Orlando gunman, Omar Mateen -- a man who was on the federal government's "no-fly list" and the FBI's radar -- could walk into a gun shop and purchase an assault weapon.
It turns out that it's perfectly legal for a person listed on the no-fly list to purchase firearms, something congressional Democrats say they want to fix, CBS News reports.
The list was created during former President George W. Bush's administration in 2001, after the terrorist attacks against the World Trade Center and Pentagon on 9/11. People who appear on the list are, by definition, suspected of involvement with terrorism either directly or peripherally. The list is maintained by the FBI's Terrorist Screening Center and is shared with agencies like the State Department.
In the wake of the June 12 shooting at the Pulse nightclub in Orlando, Florida -- which claimed 49 lives and left 53 wounded -- Democrats have become highly critical of their Republican colleagues who have blocked several attempts to pass the so-called "no fly, no buy" legislation.
Similarly, lawmakers called for no fly, no buy legislation in the wake of the Dec. 2, 2015 shooting in San Bernardino, California, which left 14 people dead and 22 injured. Rizwan Farook and Tashfeen Malik, the suspects in that shooting, were not on the national no-fly list, although they were on the FBI's radar.
That didn't prevent Democrats from ripping into Republicans after the Orlando shooting.
"The Republican majority is a wholly owned subsidiary of the National Rifle Association," House Democratic Leader Nancy Pelosi said, according to CBS News.
Presumptive Republican presidential nominee Donald Trump, who has established himself as a supporter of gun rights during his campaign, told CBS's "Face the Nation" that he would consider banning people on the no-fly list from buying guns. He made the comments in December of 2015, and on June 15 he said he was still open to the idea.
"I will be meeting with the NRA, who has endorsed me," Trump tweeted, "about not allowing people on the terrorist watch list, or the no fly list, to buy guns."
Even some supporters of gun control have been reluctant to endorse no fly, no buy. A December 2015 editorial in USA Today, published just days after the San Bernardino attack, noted that the list is "imprecise," and that a federal judge had ruled it unconstitutional because there's no way for people to know if they're on the list. There's also no protocol for removing people from the list if they're mistakenly added.
And mistakes happen, USA Today noted -- military veterans, celebrities and journalists are among those who have found themselves inexplicably added to the list, as have people who have the same or similar names as people suspected of terrorism ties.
"On the surface, the issue does seem like a no-brainer. Delve deeper than the sound bites, however, and it's a lot more complicated," the paper's editorial board wrote. "Obama, a former professor of constitutional law, should know that. Of course allowing a terrorist to buy a gun is crazy. The real question, though, is whether the no-fly list is the right tool. Until the federal government cleans up the list and the process, the answer is no."