President Donald Trump said on Monday he believed people with mental illness should be "involuntarily confined" in certain circumstances in order to prevent mass shootings.

Trump made the comments after two devastating mass shootings in El Paso, Texas, and Dayton, Ohio, that killed at least 30 people and wounded dozens of others over the weekend.

A 2015 study from the researchers Jonathan Meltz and Kenneth MacLeish of Vanderbilt University, however, found that "less than 3% to 5% of US crimes involve people with mental illness."

And when it comes specifically to mass-shooting events, James Knoll and George D. Annas wrote in 2016 that "mass shootings by people with serious mental illness represent less than 1% of all yearly gun-related homicides"

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President Donald Trump said Monday he believed that people with mental illness should be "involuntarily confined" in order to prevent mass shootings, despite research showing that people with mental illness are responsible for a tiny percentage of gun violence.

"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," Trump said, adding, "mental illness and hatred pulls the trigger, not the gun."

Trump made the comments after two devastating mass shootings that killed at least 31 people and wounded dozens of others over the weekend.

On Saturday, a gunman opened fire in an El Paso, Texas, Walmart in an attack that has killed 22 victims so far and is being investigated as an act of domestic terrorism. And a shooter in Dayton, Ohio, killed 9 people, including his own sister, in the early hours of Sunday morning.

Trump did not clarify what specific circumstances would warrant "involuntarily confinement." Most states have laws on the books allowing law enforcement to temporarily civilly commit those believed to pose an imminent danger to themselves or others.

Read more: Trump incorrectly blames 'gruesome video games' and 'mentally ill monsters' for mass violence while commenting on 2 mass shootings

A significant body of research, however, has thoroughly disproved Trump's claim that mental illness is a major contributor to mass shootings and gun violence, and does not show that involuntary confinement would likely reduce such shootings.

A 2015 study from the researchers Jonathan Meltz and Kenneth MacLeish of Vanderbilt University found that "less than 3% to 5% of US crimes involve people with mental illness, and the percentages of crimes that involve guns are lower than the national average for persons not diagnosed with mental illness."

And when it comes specifically to mass-shooting events, James Knoll and George D. Annas wrote in a chapter of the 2016 book "Gun Violence and Mental Illness" that "mass shootings by people with serious mental illness represent less than 1% of all yearly gun-related homicides," while "deaths by suicide using firearms account for the majority of yearly gun-related deaths."

Because people with diagnosed mental illnesses commit such a tiny percentage of shootings that harm other people, Knoll and Annas wrote that "laws intended to reduce gun violence that focus on a population representing less than 3% of all gun violence will be extremely low yield, ineffective, and wasteful of scarce resources," partly because "perpetrators of mass shootings are unlikely to have a history of involuntary psychiatric hospitalization" in the first place.

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