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New Report on U.S. Mass Shootings Shows That in Half of Mass Shootings, the Shooter or Shooters Displayed Warning Signs Before the Shooting

December 6, 2018

Analysis Highlights Importance of Gun Safety Policies Like Red Flag Laws, Which 8 States Have Passed Since the Parkland Tragedy

Read the Full Report Here: Mass Shootings in the United States, 2009 to 2017

Information on State Gun Laws Available On the Gun Law Navigator

NEW YORK – Everytown for Gun Safety, the country’s largest gun violence prevention organization, today released a comprehensive analysis of nine years of data on mass shootings in the United States, reporting among other findings that 51 percent of the shootings followed a warning sign of some kind — a determination that highlights the potential impact of Red Flag laws.

Everytown’s analysis also shows that in at least one-third of mass shootings, the shooter was legally prohibited from possessing firearms at the time of the shooting, a finding that comes ahead of an expected push in Congress to pass federal legislation requiring background checks on all gun sales.

“Improving our understanding of past mass shootings can help us prevent future tragedies,” said Young Nelson, senior research manager for Everytown for Gun Safety. “The clear trends in the data suggest a roadmap for policymakers. Sensible gun policies — including Red Flag legislation, stronger domestic violence laws and requiring background checks on all gun sales — can save lives.”

Analyzing data from all 173 mass shootings tracked by Everytown between 2009 and 2017, the report also finds:

  • 2017 was the deadliest year on record for mass shootings. There were four times as many people shot in mass shootings in 2017 than the average for the previous eight years.
  • In at least 54 percent of mass shootings, the perpetrator shot an intimate partner or family member.
  • Of the incidents in which information on weapon and magazine type was available, more than half – 58 percent – involved firearms with high-capacity magazines.

The report’s findings add to the growing body of research affirming the value of gun violence prevention policies, including:

  • Background checks on all gun sales
  • Red Flag laws that allow family members and law enforcement to seek the temporary removal of guns from individuals who have exhibited recent dangerous behavior. Thirteen states have Red Flag Laws on the books, including eight that passed them in 2018 alone.
  • Strong domestic violence laws that keep guns away from abusers
  • Restrictions on high-capacity magazines that limit the rounds of ammunition shooters can fire without reloading

Everytown defines a mass shooting as an incident in which four or more people,
not including the shooter, are killed with a firearm. To identify the 173 mass shootings included in this analysis, Everytown compiled data from media reports, police and court records, and publicly available databases for every identified mass shooting between 2009 and 2017.

“We cannot accept mass shootings in America as the new normal,” said Shannon Watts, founder of Moms Demand Action for Gun Sense in America. “We know that these tragedies are preventable and this analysis shows once again that there are real, effective solutions to gun violence. We must continue to use our voices to demand that our lawmakers do more to address gun violence and mass shootings, like enacting Red Flag laws, which allow family and law enforcement to intervene before deadly acts of gun violence.”

“The shooting at Marjory Stoneman Douglas High School that left 17 of my fellow classmates dead should never have happened,” said Sari Kaufman, a junior at Marjory Stoneman Douglas High School and survivor of the Valentine’s Day mass shooting in Parkland, Fla. “Law enforcement should have been empowered to remove guns from a person they knew had a long history of dangerous and violent behavior. Since the shooting, my state has passed a Red Flag law to give law enforcement the tools they need to remove someone’s guns if they are a danger to themselves or others, and I hope other states will follow suit. I don’t want what happened in my school to ever happen again.”

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