We know how to prevent school shootings, and we should stop pretending there’s nothing we can do because we lack the political will to act. There is extensive educational research showing the value of school-based programs to prevent student aggression, and there are multiple studies by the Police Foundation and others showing how shootings have been averted. These findings should spark both hope and frustration every time we hear about another student attack.

In nearly every instance, students who committed attacks had already come to the attention of adults who were concerned about their well-being.

Our analysis is backed up by a recent Secret Service study examining 41 cases of school shootings and how they could have been prevented. In nearly every instance, students who committed attacks had already come to the attention of adults who were concerned about their well-being, while their classmates knew about the potential danger as well. Typically, the students committing the assaults were victims of bullying who were angry and depressed, and had experienced mounting stresses at home and school. In each shooting, there was a missed opportunity for intervention to help a troubled student.

The most promising means of prevention is through the use of behavioral threat assessment and intervention teams. Threat assessments are designed to help schools channel assistance to students with unresolved grievances or other mental health needs, without overreacting to threats that are not serious. To work properly, the assessment process must gather information from multiple sources and consider the context and intent of the student’s statements. In the vast majority of cases, a student’s threatening statement does not pose a serious risk of violence and can be resolved with counseling and education.

Such intervention teams were recommended by the FBI, the Secret Service and the U.S. Department of Education after the 1999 Columbine shooting. Over the past 18 years, controlled studies at the University of Virginia found that well-trained multidisciplinary school teams have resolved thousands of student threats without any serious injuries, and at the same time have been able to help troubled students and keep them in school.

In almost all cases, a student making threatening statements is responsive to intervention. In Virginia, where all public schools have been required to have threat assessment teams since 2013, only about 1-2 percent of students receiving a threat assessment are arrested, with even fewer expelled from school. The process has been conducted without racial disparities and has produced a decline in out-of-school suspensions.

Over the past 20 years, however, schools have been slow to adopt threat assessment. Instead, they have pursued two common practices that scientific research has found do not work. First, schools continue to invest billions of dollars annually in building security measures, many of which were in place in the schools that experienced attacks. Multiple studies have concluded that physical security measures are not linked to increased safety; on the contrary, they increase student fears.

Second, many schools persist in a “get tough” zero-tolerance approach to school discipline that removes students from school for even the smallest violations. This highly punitive practice runs counter to more than a decade of research showing that exclusionary discipline does not improve student behavior or make schools safer. Instead, routinely suspending students is associated with academic failure, increased misbehavior, a higher dropout rate and later involvement with the criminal justice system.

Schools have also become hypersensitive to student misbehavior and are actively searching for potential warning signs, such as using internet surveillance systems to monitor websites for threatening posts. Without a standardized threat assessment process, authorities can overreact to student expressions of anger or frustration that aren’t truly dangerous.

Since the 2018 shooting in Parkland, Florida, states have started to act and use threat assessment more widely. Nevertheless, there are substantial barriers. Schools are being pressed by legislatures to implement new programs too quickly without adequate training and quality control. Most school systems in the U.S. have fewer than half the recommended number of counselors, psychologists and social workers. And there are objections from civil rights groups that the process might stigmatize students or expose private information if not properly conducted. But these are solvable problems if schools are adequately funded and trained to conduct threat assessments with evidence-based practices.

Until now, there has been too much emphasis on reactive approaches and too little attention to proactive prevention. Schools need multi-tiered systems of support to encourage positive student behavior and a curriculum that includes social emotional learning as well as traditional academics. These programs help at-risk students cope with stressors and form positive social relationships where they can be productive members of their school community.

A large body of research has also demonstrated the importance of a positive school climate, where students feel connected to their schools and respected and supported by staff. Such a climate is essential for students to come forward when they learn about a threat or simply recognize that a classmate is in distress and needs help.

Mental health professionals, teachers and families working together are the most effective way to prevent more shootings.

In addition, it is important to acknowledge that access to guns plays a key role in the extremely high rate of shootings across the United States. Our political leaders must find a reasonable and constitutional pathway to limit the widespread availability of firearms to persons who cannot use them in a responsible, lawful manner.

After every school shooting, we hear lamentations about our inability to keep our children safe from violence. However, the Secret Service study and dozens of others tell us what we need to do: Schools are safest when we attend to the mental health and well-being of our youth. Schools need the resources to obtain high-quality training to conduct appropriate threat assessments, and the mental health staff to meet the needs of troubled students. Mental health professionals, teachers and families working together are the most effective way to prevent more shootings. It’s time to put politics aside and take action based on evidence.