Myths About Mass Shootings
After a mass shooting like the June 24, 2018 shooting at a North Carolina dance studio leaving one dead and six seriously injured or the February 14, 2018 school shooting in Parkland, Florida which left 17 people dead and 17 more wounded, many wonder if such incidents could have been prevented. They try to determine if there were warning signs that should have been noticed, whether the person had a mental illness, or if the shooter held extreme views on politics or the Middle East.
Even before the final death count had been reported from the shooting spree in Parkland, Florida, politicians, policy makers, mental health professionals, and other experts could be found on the media, voicing their proposals for change. Some talked about gun control, others about mental health screenings, and still more about the need for better security in schools and other public places. Whatever the these individuals made certain assumptions concerning patterns they believed could be found based on profiles created from aggregated data of mass killers. Unfortunately, these assumptions were not always consistent with the facts. These beliefs also failed to recognize that predicting such violence is almost impossible based on common characteristics.
One of the main aspects that has been assumed to be useful in predicting future violence is mental illness. Following the Parkland shooting, President Trump called for a greater focus on mental health problems and care as a means of stopping future mass shootings. However, while it is easy to assume that those who commit such crimes must be mentally ill, the idea that mental health difficulties predispose someone to mass violence is, in large part, a myth. This means mental illness factors cannot be used to predict this type of crime, and increasing screening and treatment, while important in their own rights, will not likely affect future gun violence.
Another problem that make prediction of mass shootings incredibly difficult is the fact that these types of shootings are extremely rare. The vast majority of people in the U.S. and elsewhere will never commit a mass shooting, despite there being a problem in America with gun violence. Even estimating that one in a million people will become mass shooters would be much too high. Given that of the approximately 323 million people in the U.S. almost none will become mass murderers, this makes prediction practically impossible. This is due to the realities of statistics and how they lend themselves to the power of prediction. The rarity of these types of shootings and the fact that most shooters are deceased also means we have limited data to use for prediction.
Probability and Predicting Mass Shootings
Myth: A strong enough prediction model could reliably predict future shootings.
Our inability to determine who could be a mass shooter comes down to statistics and the power of prediction models. This can be best explained through a hypothetical example.
Let’s say that we have a prediction model that is 95 percent accurate. This of course is imaginary as we can’t even predict the weather accurately 95 percent of the time, much less human behavior. However, for the purposes of this example we’ll assume it. This would be considered a great model and one most of us would be willing to trust.
Now let’s say that one in a million people will become a mass shooter. This is also an overestimate since we know the incidence rates of such crimes are far less. So this means that in a sample of one million people, our prediction model will label 95 percent of the harmless people accurately. It should also pick up the one who will become a mass shooter. This seems like good news. What’s the problem.
The problem comes when you realize the prediction model will identify five percent of the harmless people as potential mass shooters along with the one who really is the future murderer. This means in addition to the correctly identified future shooter, the model will also identify 50,000 people who won’t go on to become shooters. We will then simply have narrowed our odds down to knowing that one person in this group of 50,001 people will become a mass murder. This isn’t very useful information.
Other Statistical Reasons That Prevent Prediction of Mass Shooters
Myth: if you use the right statistics you could find what factors predict future shootings reliably.
When conducting research, you need enough data points, in this instances cases of mass shootings, to be able to determine a real effect. In other words, you need a large number of shooters that you have information about to be able to use that information to reliably predict future shootings. When there is too few cases or data points, this means there is low statistical power and you are unlikely to find any meaningful results.
A study with limited statistical power has two problems. First, there is a decreased chance of detecting a real effect when it exists. So if certain factors exist that could reliably predict future shootings, the low number of cases means that you won’t likely determine what these factors actually are.
At the same time, low statistical power means that when you do find statistically significant results, these results are unlikely to reflect a real effect. This means that even if your prediction model has indicated there is a specific factor that predicts future shootings, it is probably this is an inaccurate finding.
Prediction from Warning Signs
Myth: We know enough about warning signs that if we had proper screening techniques we could predict mass shootings.
Most of the attention related to mass shooters has focused on identifying warning signs. The fact is that we do have some information about features that have been found in what is considered to be the typical mass shooter.
For example, 95 percent of mass shooters are male, 67 percent are caucasian and they tend to be older than murderers overall. About 50 percent of mass shooters are over the age of 30, 38 percent are between the ages of 20 and 29 and slightly over 12 percent are under the age of 20.
Common psychological factors that have been determined in these individuals include depression, anxiety, resentment of others, social isolation and withdrawal. They tend to externalize blame or blame others instead of accepting responsibility for their problems. They also often have an interest in violent entertainment and a fascination with weapons, guns in particular.
Yet even knowing all this, it is still almost impossible to determine who might become a multiple shooter before the fact. This is because these characteristics are fairly prevalent in the general population. For example, it has been estimated that about 20 percent of the U.S. adult population suffers from a mental disorder at any time. This amounts to more than 60 million people. We also know that the vast majority of people with mental illnesses are not violent. So although mass shooters share common characteristics most people with those characteristics are not dangerous and do not turn out to be mass murderers. Without risk factors that are specific to mass shooters or even those prone to gun violence or murder, we cannot predict future shootings.
Although there are apparently certain characteristics that are common in mass shooters, this does not mean we can use them to predict the next one. There are two main reasons this is the case. First, prediction models will grossly overestimate who could become a future shooter, providing largely useless information.
The second reason is that the characteristics found in mass shooters are common in the overall population even in combination. However, the vast majority of people with those features are not mass murderers or even violent. Many people may closely resemble the profile for mass shooters. They may be angry, and frustrated about work, school or homelife. They may be withdrawn and reclusive, quick to blame others for their problems and they may even make threatening remarks. However, very few if any of these people will go on to commit murder, much less mass murder.
This also applies to the most commonly referenced factor, mental illness, despite the automatic assumption that anyone who commits such a crime must be mentally ill. While some individuals who become mass shooters appear to have mental health issues, these issues are only identified as problematic after the fact. The fact remains that most people with mental difficulties are not dangerous. While increased and better-funded interventions for mental illness is clearly a great thing, it ultimately won’t have much of a direct effect on mass shootings. Sometimes these shooters have a history of mental illness, or are currently mentally ill, but many individuals who commit mass shootings are not mentally ill in any diagnosable way. Not to mention that the vast majority of those with mental illness do not harm others or become mass murderers as a function of their difficulties.
Although gun control is controversial in the U.S., it is possible that controlling gun access can go hand in hand with mental health treatment to prevent tragedies including mass shootings. Many people with suicidal or homicidal intent are fixated on certain methods of carrying out the impulse. When something blocks their ability to use the method on which they have settled, sometimes that is enough to throw them off balance and delay them in carrying out the deed. This may also make them open to the possibility of getting help which may prevent the action entirely. So while it may not solve the entire problem, limiting access to guns even if there is only a waiting period, may derail an impulse long enough for the person to solve their perceived problem in a different way. If the person decompensates further this may also result in helping them come to attention of someone else who might get them the help they need if they themselves are not in a place to do so.
While this may not address many possible mass shootings in the case of those individuals who meticulously plan their attacks, there is evidence from other countries that limited gun access is related to lower mass shooting rates. One study examining data from 171 countries for the years 1966 through 2012 suggested that rampage shootings were at least partially attributable to differences in firearm accessibility. This study seem to lend support to the possibility that the U.S. and other countries with high rates of gun ownership may be particularly susceptible to future mass shootings. This may be the case even if these countries can be seen as relatively peaceful or mentally healthy based on other national indicators.
When all is said and done, the main questions, I find myself left with after struggling with the fact there seems to be nothing that will consistently eliminate these murderous rampages are these:
Has violence become viewed as something we just have to accept? Or, worse, has it perhaps become a core value of our culture? Is violence now seen as a way of getting what we want or getting revenge we feel we are owed when nothing else seems to work? Most importantly, if the answers to these questions are yes, where does that leave us as individuals and as a nation?
Deadliest Mass Shootings in the U.S. Since 2000
10 killed - May 18, 2018 - Ten children and one teacher are killed and 10 others wounded in Santa Fe Texas, when a 17 year old student opens fire with a shotgun and a revolver. Explosive devices including pipe bombs and pressure cooker devices were found in and around the school placed by the suspect. The shooter was captured unharmed.
17 killed - February 14, 2018 - Seventeen adults and children are killed at a high school in Parkland Florida by Nikolas Cruz a former student. He is charged with 17 counts of premeditated murder.
25 and an unborn child killed - November 5, 2017 - A lone gunman begins shooting at a church in Sutherland Springs. Before it’s over, 25 people are killed. One woman killed was pregnant, bringing the total to 26. Twenty others were wounded. The killer, Devin Patrick Kelley, is found dead though it’s unclear if the gunshot that killed him was self-inflicted.
58 killed - October 1, 2017 - A gunman, later identified as Stephen Paddock, opens fire on a crowd of people attending a concert in Nevada. The gunshots continue for around 15 minutes, according to witnesses. Fifty-eight people are killed and over 500 injured. Paddock is found dead after police believe he shot himself.
49 killed - June 12, 2016 - Forty nine people are killed and 58 wounded in a hate crime inside a gay nightclub in Orlando, Florida. The shooter, Omar Mateen, is shot and killed by police who are attempting to free hostages following a standoff lasting over three hours.
14 killed - December 2, 2015 - Syed Rizwan Farook and Tashfeen Malik, a married couple, kill 14 employees and injures 22 others at a gathering in San Bernardino, California, during a shooting rampage. Both perpetrators are shot and killed by police.
9 killed - October 1, 2015 - Armed with three pistol and a rifle, Christopher Sean Harper-Mercer shoots and kills nine people at Umpqua Community College in Roseburg, Oregon. Nine others are injured. Harper-Mercer is killed during a shootout with police.
9 killed - June 17, 2015 - Dylann Roof, shoots nine people at the historic Emanuel African Methodist Episcopal Church, in Charleston, South Carolina. Eight die at the scene and the ninth dies at a hospital. Roof tells investigators after being arrested the next day he intended to start a race war. Roof is convicted of murder and hate crimes and sentenced to death. If carried out, he would be the first person executed for committing hate crimes.
12 killed - September 16, 2013 - A shooting rampage, carried out by Aaron Alexis, a former navy reservist, occurs at the Washington Navy Yard, in northern Virginia kills 12. Alexis was shot and killed by police.
27 killed - December 14, 2012 - In Newtown, Connecticut, Adam Lanza kills 20 six and seven year old children and six staff and faculty at Newtown Elementary School. Lanza shoots himself and later his mother is also found dead from a gunshot wound.
12 killed - July 20, 2012 - At a screening of the new Batman film in Aurora, Colorado, James E. Holmes sets off two bombs which he follows with a spray of bullets from an AR-15 rifle, a 12-gauge shotgun and two .40-caliber handguns. When it is over, 12 people are dead and 58 are injured. Holmes is convicted on 24 first-degree murder charges, 140 attempted murder charge and a possession or control of an explosive or incendiary device charge. He is sentenced to life in prison without the chance of parole.
8 killed - October 12, 2011 - Eight people are killed during a shooting at the Salon Meritage in Seal Beach, California. Scott Evans Dekraai, shoots and kills eight people at a salon in Seal Beach, California, including his ex-wife. When he is arrested, he is armed with a 9 mm Springfield, a Smith & Wesson .44 Magnum, and a Heckler & Koch .45. Dekraai is convicted and sentenced to eight terms of life in prison without parole, plus an additional 232 year to life term for attempted murder.
8 killed - August 3, 2010 - In Manchester, Connecticut, Omar Thornton is asked to resign after he is caught stealing and selling alcohol. He kills eight co-workers at Hartford Distributors then shoots himself.
13 and an unborn child killed - November 5, 2009 - A U.S. military psychiatrist, Maj. Nidal Malik Hasan opens fire on unarmed soldiers, at a military base at Fort Hood in Texas. He is shot by police and paralyzed from the waist down. Hasan is found guilty of 14 counts of premeditated murder and 31 counts of attempted premeditated murder and is sentenced to death.
8 killed - March 29, 2009 - In a Carthage, North Carolina nursing home, Robert Stewart shoots and kills a nurse and seven elderly patients. He is found guilty of second-degree murder. The district attorney seeks the death penalty but Stewart is sentenced to 141-179 years in jail.
13 killed - April 3, 2009 - After being laid off, Jiverly Wong shoots and kills 13 people and injures four other at an immigrant community center in Binghamton, New York. He then kills himself.
10 killed - March 10, 2009 - Michael McLendon leaves 10 dead in a shooting spree in three different communities in southern Alabama. Those killed include his mother, uncle, two cousins, great aunt, a neighbor and wife of a police officer and their infant daughter. Also killed were a motorist, a woman outside a convenience store and a man who tried to run away and was shot in the back. McLendon was corned at a metals plant and he killed himself when police started shooting. Six others were wounded. When he was killed, McLendon was armed with a handgun, two assault rifles and a shotgun. Police said it looked as if he intended to keep killing people at the plant as his car was filled with more guns and ammunition.
8 killed - December 5, 2007 - In Omaha, Nebraska, 19-year-old Robert Hawkins goes to an area mall, enters the Von Maur department store, shoots and kills eight people and critically wounds four others. He then turned the gun on himself and committed suicide.
32 killed - April 16, 2007 - Another school shooting occurs at Virginia Tech in Blacksburg, Virginia, Seung-Hui Cho, guns down 32 people in two locations and wounding dozens of others on campus. Cho commits suicide before police can apprehend him.
9 killed - March 21, 2005 - At Red Lake High School, in Minnesota, Jeff Weise a sixteen year old, kills his grandfather and his grandfather’s partner at their home. He takes his a Glock pistol and a shotgun and heads for his high school. He shoots and kills five classmates, a teacher and a security guard then kills himself. While many of the kids knew of Weise’s interest in school shootings, there was no motive ever discovered.
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© 2018 Natalie Frank