On Feb. 15, 2018, a shooter armed with a semiautomatic rifle walked onto the campus of Marjory Stoneman Douglas High School in Parkland, Florida, and opened fire, killing 17 people while students barricaded themselves inside classrooms and hid inside closets in a desperate effort to protect themselves. Police eventually captured a 19-year-old former student, Nikolas Cruz, who had recently been expelled from school for disciplinary reasons [source: Rozsa, et al].
For a nation that has seen a string of mass shootings over the past two decades, it was yet another collective trauma. "I'm kind of surprised it happened here, but I'm not really shocked," one Parkland student told the Washington Post. "School shootings happen all the time, and then the news just forgets about them."
What was even more shocking to some was the ease with which Cruz, who reportedly had a history of emotional problems and menacing behavior, had been able to obtain weapons. CNN, citing a law enforcement source, reported that Cruz had acquired 10 rifles in the year or so prior to the attack [sources: McLaughlin and Park, Fausset and Kovaleski].
And once again, as they have so many times in the last, gun control advocates called for stricter laws to prevent such tragedies. "I want everybody to know we've been here before, and it's horrifying to think of the lives that are lost every day to gun violence while we sit here in Congress," proclaimed Sen. Dianne Feinstein, D-Calif, who the previous year had introduced a proposal to bank military-style assault weapons and high-capacity magazines.
Tragic events spark fear and outrage, drive up gun sales and, conversely, inspire calls for expanded (or better-enforced) gun control [source: Ingram]. This has been the pattern for the past half-century, since Congress passed the Gun Control Act of 1968 following the assassinations of Robert F. Kennedy and Dr. Martin Luther King Jr. The Brady Act, which requires background checks by licensed dealers (but does not apply to gun shows), arose from the 1981 assassination attempt on Ronald Reagan [sources: ATF; Hennessey and Mascaro; The New York Times]. The act is named for James Brady, Reagan's press secretary who also was injured in the attempt and went on to become a gun control advocate.
The possibility of legal reform remains unclear, and the composition and effectiveness of such laws remains hotly debated.
One proposed gun law reform involves banning assault weapons such as the popular AR-15, the semi-automatic rifle used in numerous mass shootings, including the 2012 attack on Sandy Hook Elementary School in Newtown, Conn., which took the lives of 20 young children and six teachers, and the slaughter of 59 people by a gunman who fired on a concert from a hotel room window in Las Vegas in October 2017 [source: Blankstein, et al., Calabrese and Siemaszko]. Such a ban was passed by Congress in 1994 and stayed in place for a decade, before it was allowed to lapse in 2004. Attempts to revive the measure have failed, due to both divergent views and the difficulty in codifying a workable and non-exploitable definition of "assault weapon" [sources: Haas; Kucinich; Lawrence; New York Times].
But after the 1994 law was passed, public support for gun control receded. In 1991, a Gallup poll found that 78 percent of Americans favored stricter gun laws, but by 2011, the year before Sandy Hook, just 44 percent of Americans supported it. But since then, perhaps driven by repeated instances of mass killings in recent years, it's started to rise again, so that by the beginning of 2018, 60 percent again were in favor of stricter laws [source: Gallup] A poll conducted by Quinnipiac University in the wake of the Parkland mass shooting found strong support for various gun control measures. Sixty-seven percent of Americans favored revival of the assault weapons ban, and 97 percent favored universal background checks on gun purchasers. Currently, people can avoid such screening if they buy from private owners or at gun shows [sources: Quinnipiac, Cook].
In the U.S., the gun control debate comprises strongly held views about constitutional law, the rights of the individual, the role of the state and the best way to keep society safe. But it also encompasses an important practical question: Do countries with stricter gun laws experience less crime or fewer homicides?
The answer is anything but simple.
Violent Crime and Guns
The fight for more stringent gun control laws derives in part from the idea that more guns mean more violence. As it turns out, though, in the United States and the rest of the developed world, total murder and suicide rates, from all causes, do not increase with rates of gun ownership -- or drop under tougher gun laws [sources: Killias, van Kesteren and Rindlisbacher; Liptak].
The effect of gun laws on gun-related violence is fuzzier and far more controversial but, in general, more guns mean more gun-related violence [sources: Killias, van Kesteren and Rindlisbacher; Liptak; Luo]. We'll examine this further below.
First, let's look at the relationship between gun laws and violence in general. It is possible to have a violent society without guns. Prime evidence of that is the former Soviet Union and its successor states such as Russia, which despite stringent gun control laws, posted murder rates from 1965-1999 that far outstripped the rest of the developed world [sources: Kates and Mauser; Kessler; Pridemore]. The killers in question did not obtain illegal firearms -- they simply employed other weapons [source: Kleck].
On the other hand, Norway, Finland, Germany, France and Denmark, all countries with heavy gun ownership, have a history of low murder rates. According to a 2014 United Nations report, Germany's murder rate of 0.8 killings per 100,000 inhabitants was identical to Luxembourg, where the law prohibits civilian ownership of handguns and gun ownership is rare [source: UNODOC, Kates and Mauser].
The U.S., though, in many ways is a special case. Not only does it have more guns than any other nation on the planet, but it also has far more gun deaths than any other developed nation — six times the homicide rate of neighboring Canada, more than seven times as many as Sweden, and 16 times as many as Germany [source: Lopez].
Within the U.S. picture isn't as uniform, because in addition to federal regulation, states across the U.S. have their own varying laws on firearms. Opponents of gun control often point to the city of Chicago, which had 781 homicides and 3,000 shooting incidents in 2016, despite Illinois' relatively tough gun laws, as proof that gun control doesn't work [source: Lewis].
But one recent study suggests that stricter state gun laws do make a difference. In a study published in the May 13, 2013 issue of JAMA Internal Medicine, researchers concluded that states with the most firearm legislation have the lowest rates of firearm-associated deaths, as well as the lowest rates of both murders and suicides with guns. The quarter of states with the strictest laws had 6.64 fewer deaths per 100,000 inhabitants than the quarter with the least regulation [source: Fleegler, et al.]
A 2013 UN study came to a similar finding. "While the specific relationship between firearm availability and homicide is complex, it appears that a vicious circle connects firearm availability and higher homicide levels," it concluded.
Causation, Conflation and Consternation
One of the reasons gun debates are so difficult to settle, aside from the strong feelings involved, is that the data involved in researching connections between gun laws, gun ownership, gun crime and non-gun crime are frequently mixed, murky, misrecorded and difficult to compare.
Take the United Kingdom, where ever-more stringent gun bans brought gun-related homicides to among the lowest in all of Europe from 2003-2010, but where guns remain widely available and are increasingly used in the commission of violent crimes [sources: BBC; UNODC].
In the U.S., crime rates have dropped significantly since the early 1990s, and continued to decline into the 2010s, even as gun sales increased, leading some opponents of gun control to argue that more guns actually help to deter crime [source: Bell]. But other analysts argue that other factors — such as the aging of the U.S. population — account for the drop [source: Lind and Lopez]. Still others point to the significant uptick in American prison populations and executions during this period, or to the larger police forces and improved crime-fighting tactics, the flagging crack-cocaine trade, the booming economy, even the legalization of abortion in the early 1970s, which prevented many births to poor single mothers as reasons for declining crime rates [sources: Lott and Mustard, Donohue and Levitt].
The point is, the "more guns = more violence" argument and the "gun ownership = decreased crime" argument both sidestep the complicating socioeconomic, cultural and psychological factors affecting violent crime. Economic disparities within countries, along with periods of economic downturn, drive up crime and homicides, and violent crimes occurs four times more often in countries with wide income gaps. While economic prosperity tends to decrease violent crime, crime itself can depress community development, perpetuating a cycle of poverty and violence [source: UNODC].
Violent crime arises from more complicated causes than guns, yet there is no question that guns are associated with a particularly brutal brand of crime. Removing guns from the equation might not stop violence altogether, but might it prevent another Newtown?
The Unique Problem of Guns
Some opponents of gun control, including NRA Executive Vice President Wayne LaPierre, say, "The only thing that stops a bad guy with a gun is a good guy with a gun" [source: Lichtblau and Rich]. But at least one study has shown that defensive gun use succeeds only rarely, and that gun owners are 4.5 times more likely to be shot during an assault [source: Branas, et al.]
It's hard to say how many mass shootings might have been prevented with tighter gun control laws. Because of the gun show loophole, the woman who bought three of the four guns used by the Columbine killers was never prosecuted, despite making a "straw purchase" for two minors [source: Violence Policy Center]. 2007 Virginia Tech massacre gunman Seung-Hui Cho passed a background check to purchase his weapons, even after a state judge had declared him mentally ill [source: Schmidt and Savage].
But work by University of Massachusetts researcher Louis Klarevas suggests that revival of the federal assault weapons ban might reduce the number of mass killings. For his 2016 book "Rampage Nation," Klarevas gathered data on every mass shooting incident in which six or more people were killed between 1966 and 2016. He found that compared to the 10-year period before the 1994 ban took effect, the number of such massacres dropped by 37 percent, and the number of fatalities decreased by 43 percent. But after the ban expired in 2004, the number of mass killing incidents increased by a startling 183 percent, and fatalities jumped by 239 percent [source: Ingraham].
But to really limit mass shootings, some say that it also will be necessary to find effective ways to identify and treat the mentally ill, and to limit their access to sensitive areas and weapons. Proponents of closer screening have complained that states aren't always diligent in submitting mental health records to the federal background check database, despite a 2007 federal law requiring it. They can point to the example of Jared Lee Loughner, who killed six people and wounded 18 others, including then-U.S. Rep. Gabrielle Giffords, D-AZ, in 2011. Though Loughner was suspended from a community college because of mental health problems, he still managed to pass a federal background check and purchase a weapon. The Brady Campaign to Prevent Gun Violence, a gun control group, estimated at the time that millions of mental health records were missing [source: Feldmann]. Preventing violent acts like this will require understanding and defusing the pathology that drives these killers -- a feat far easier said than done.
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