Research does not support blaming mass shootings on mental illness

NEW YORK (WABC) -- Mental health professionals pushed back Monday to President Donald Trump's assertion that mental illness is the culprit for recent mass shootings in the United States.

"We must reform our mental health laws to better identify mentally disturbed individuals who may commit acts of violence and make sure those people, not only get treatment but when necessary, involuntary confinement. Mental illness and hatred pulls the trigger, not the gun," President Trump said.

The American Psychological Association responded to comments regarding mental illness and mass shootings reiterating that mental illness does not necessarily lead to violence and adding that stigmatizing mental illness will discourage people who are struggling from seeking treatment.

"Routinely blaming mass shootings on mental illness is unfounded and stigmatizing," said American Psychological Association President Rosie Phillips Davis in a statement. "Research has shown that only a very small percentage of violent acts are committed by people who are diagnosed with, or in treatment for, mental illness. The rates of mental illness are roughly the same around the world, yet other countries are not experiencing these traumatic events as often as we face them."

Eyewitness News examined several studies examining factors that may contribute to the occurrence of mass shootings.

One study provided by the National Institutes of Health found fewer than 5% of gun-related killings were perpetrated by people diagnosed with mental illness.

That same study found a direct connection between an increase in gun violence and states with increased gun ownership and lenient gun laws.

"Certainly the stats play out in places where there are more guns," said Brad Garrett, ABC News Crime and Terror Analyst.

Additionally, a Homeland Security study into mass shootings found 75% of attackers showed signs that they were about to attack.

An FBI study found that four out of five active shooters display concerning behaviors as subtle as a change in work performance.

Research also shows that 59% of the time people around the mass shooter did not report odd behavior to law enforcement.

"It's fairly common for people to have some information that a professional will look at and say, 'Oh my goodness, this kid is in trouble,'" Garrett said. "What happens is they feel more and more angry toward society. You will see these people go into a downhill slide."

Garrett said mass shooters tend to be white males who have struggled socially and professionally and tend to feel, "outside of society."

He said preventing a shooting or other violent acts often requires early intervention likely by elementary or middle school.

"If you think that you're going to treat somebody at 18, 19, 20 or older, it's a lot more difficult to do," Garrett said.

Threat assessment psychologist Marisa Randazzo added that preventing mass shootings is possible.

"It's possible to prevent mass shootings because these events are planned in advance and most importantly those who carry out mass shootings typically tell others about it beforehand," Randazzo said. "It's okay for people to report behavior at low levels. Law enforcement wants to hear about it."

Below is a list of potential warning signs someone could become violent provided by the APA.

Some signs of potential for violence may be historical or static (unchangeable) factors like:

  1. A history of violent or aggressive behavior
  2. Young age at first violent incident
  3. Having been a victim of bullying
  4. History of discipline problems or frequent conflicts with authority
  5. Early childhood abuse or neglect
  6. Having witnessed violence at home
  7. Family or parent condones use of violence
  8. A history of cruelty to animals
  9. Having a major mental illness
  10. Being callous or lacking empathy for others
  11. History of vandalism or property damage

Other signs of potential violence may be present over time and may escalate or contribute to the risk of violence given a certain event or activity. These might include:

  1. Serious drug or alcohol use
  2. Gang membership or strong desire to be in a gang
  3. Access to or fascination with weapons, especially guns
  4. Trouble controlling feelings like anger
  5. Withdrawal from friends and usual activities
  6. Regularly feeling rejected or alone
  7. Feeling constantly disrespected

Some signs of potential violence may be new or active signs. They might look like:

  1. Increased loss of temper
  2. Frequent physical fighting
  3. Increased use of alcohol or drugs
  4. Increased risk-taking behavior
  5. Declining school performance
  6. Acute episode of major mental illness
  7. Planning how to commit acts of violence
  8. Announcing threats or plans for hurting others
  9. Obtaining or carrying a weapon

There is research that indicates that new or active signs are more predictive of short-term risk of violence than historical factors, which may be more predictive of longer-term risk.

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