Here’s one of the best things schools can do to prevent mass shootings

Students stood in silence for 17 minutes as they participated in a walkout to protest gun violence, in Hagerstown, Md., on Wednesday.Colleen McGrath/The Herald-Mail/AP

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In 2001, New Bedford High School narrowly missed a devastating attack.

A group of students had plotted to shoot and kill their peers at the school in an attack mimicking the massacre two years earlier at Columbine High School in Colorado. They allegedly vowed to use the school’s security cameras to capture the violence on tape, then go to the building’s roof to celebrate with drugs and alcohol before killing each other.

The massacre never happened. One student got scared and told a trusted teacher of the plan. An investigation was launched and the students were arrested, and ammunition and bomb-making instructions were later found in their homes.

The foiled plot is considered one of the earliest examples of how schools can use what are known as “threat assessment teams” as a first line of defense against potential violence.

“Prevention must start before there is a gunman at the door,” Dewey G. Cornell, a forensic clinical psychologist, education professor, and director of the Virginia Youth Violence Project at the University of Virginia. “There is a lot we can do to prevent violence rather than simply prepare for an attack.”

Threat assessment teams typically consist of a mix of teachers, staff, mental health professionals, and law enforcement who get trained in how to gather information about potential threats, including tips from school community members, and then to evaluate how credible and serious the threat is and intervene accordingly.

Since the New Bedford case, the idea has been backed by further research and such teams have been launched in schools throughout the United States.

Debate is fierce over whether other measures — such as stricter gun laws, school building security systems, or armed teachers and guards — can make a difference when it comes to preventing school shootings.

But a broad consensus of researchers, government agencies, and advocacy groups agree that well-run threat assessment teams have proven to be an effective step.

Assembling a team of stakeholders from across the school community and training them to look proactively for issues, experts say, is key to rooting out troubles that might push a student toward a violent path — problems like bullying, turmoil at home, and isolation.

“People who carry out mass violence usually do so because they’re under some personal distress,” said Marisa Randazzo, a former research psychologist for the Secret Service who is now director of Georgetown University’s threat assessment program and principal and co-founder of SIGMA Threat Management Associates.

“That’s why this works to help prevent mass shootings,” she said. “You figure out, ‘Why do they want to do this in the first place, and how do we help them deal with those issues in another way?’”

Specialists said that, for the teams to work well, other steps should be taken in addition to creating the teams, including bolstering services such as mental health and counseling that can be keys to successful intervention.

It’s also vital that schools improve so-called bystander reporting by ensuring that students, especially, feel comfortable coming forward to report, anonymously or otherwise, if they encounter something concerning.

“Kids often plan these things out for a period of time and they tell other people and in the vast majority of cases, kids tell other kids,” said Eric Madfis, associate professor and degree chair of criminal justice at the University of Washington, Tacoma.

A 2004 federal study examined 37 incidents of targeted school violence where a lethal weapon was used (guns, in most cases) between December 1974 and May 2000. It found in 30 of the cases “at least one person had information that the attacker was thinking about or planning” the attack.But in only two of the cases did an adult have such information.

Government agencies that back the threat assessment model, include the FBI, as well as the US Department of Education and the Secret Service, which have jointly studied the concept.

The Trump administration is supporting a bill before Congress that would provide federal grant funding for threat assessment teams and other school safety measures. The administration announced it is creating a commission to study and make recommendations about school safety, including threat assessment best practices.

Safety experts said they were not aware of exact counts of how many K-12 schools in the United States have threat assessment teams, but they estimated the number is at least in the thousands.

A public safety law approved in Florida last week in the wake of the Parkland shooting requires schools there to have the teams. A study last year found that only one other state, Virginia, explicitly requires schools to have the teams. But it found that at least five other states — Nebraska, New York, Rhode Island, Tennessee, and Washington — have policies that imply the need for such teams or something similar. Another 17 states, including Massachusetts, have school safety plans encouraging and offering guidance on threat assessment.

Massachusetts education officials said many districts have trained teams in place, but they do not track data on which do.

Boston Public Schools officials said they have trained threat assessment teams at every school districtwide, along with a centralized team offering additional support.

Andria Amador, the district’s senior director of behavioral health services, said the teams have proven to be a valuable tool, but they need to be coupled with other measures, such as mental health and counseling support. “Threat assessment is a piece of a broader part of creating safe and supportive schools,” she said.

While encouraged that more schools have established threat assessment teams, specialists said they worry some schools aren’t putting enough energy and resources into creating quality teams or investing in related measures, such as encouraging bystander reporting.

For example, while New Bedford Public Schools officials said they continue to follow the model to respond to students in crises — “That’s become embedded as part of the culture,” said Andrew B. O’Leary, the district’s business manager — they also noted federal funding for such programming has been cut over the years. “So much more could be done if that level of support was restored.”

Experts also say some schools around the country have become so obsessed with more visible safety measures, such as upgrading their building security or practicing active shooter drills, that they’ve lost sight of investing in efforts, like threat assessment, that can potentially prevent attacks in the first place.

Virginia, where threat assessment teams have been required at public schools since the 2012 Newtown, Conn., school shooting, is an example of how the teams can be beneficial, but also are challenging to run well.

“There is evidence from statewide studies that K-12 schools using threat assessment have been able to resolve thousands of threats without violence,” Cornell, the University of Virginia professor, said in a recent statement.

But, he added: “Statewide surveys have found that only 50 percent of Virginia K-12 teachers know that their school has a threat assessment team. Also troubling is that state funding to train school teams has fallen off the state’s priority list — and despite the state mandate, 34 percent of Virginia schools reported that they did not conduct any threat assessments last year.”