Preventing school shootings works best as overlapping layers rather than any single fix. The research, law enforcement analysis, and post-attack reviews of the last two decades point to the same core answer on how to prevent school shootings: build a school climate where students report warning signs, train a team to act on those reports, keep firearms locked away from the minors who commit most of these attacks, make mental health help available, and give courts a way to remove guns from people in crisis. Physical security, drills, and armed staff sit behind that system as backstops, and the evidence for them as primary strategies is thin.
The layers matter because attackers almost always leak their plans. A 2021 U.S. Secret Service National Threat Assessment Center analysis of 67 disrupted plots against K-12 schools between 2006 and 2018 found that in every averted case, someone came forward with information that let authorities intervene. “Individuals contemplating violence often exhibit observable behaviors,” the report concluded, “and when community members report these behaviors, the next tragedy can be averted.”1 Prevention is largely a question of whether the observation reaches the right adult in time.
Behavioral Threat Assessment
Behavioral threat assessment is the concept that ties nearly every prevention framework together, from the Secret Service to individual school districts. A multidisciplinary team — administrators, counselors, school psychologists, sometimes law enforcement — gathers information when a student is reported for concerning behavior, evaluates the level of risk, and puts together an intervention. That intervention might be counseling, a mental health referral, family engagement, or discipline, depending on what the situation calls for.
The approach has become widespread. As of October 2025, 45 states have established some form of behavioral threat assessment policy for schools, and 85 percent of schools reported having a threat assessment team in place as of April 2024. NTAC alone has trained nearly half a million people across schools, law enforcement, and businesses on these principles.
The kinds of behaviors these teams look for are not subtle in hindsight: direct threats, an obsessive interest in past attackers, escalating anger, talk of self-harm, sudden interest in weapons, and a deteriorating home or school situation. Ethan Crumbley drew images of a gun and bloodshed on a school assignment the morning of the Oxford High School shooting. Colt Gray’s father was later shown to have known about his son’s interest in past school shooters and his deteriorating mental health before the Apalachee High School attack. The warning signs were there. The question in each case was whether anyone acted on them.
The evidence on threat assessment is promising but comes with a real caveat. Research on the Comprehensive School Threat Assessment Guidelines model shows that high-fidelity implementation is associated with fewer long-term suspensions, reduced bullying, and increased access to counseling. Poorly implemented programs can do the opposite, criminalizing students, worsening racial and disability-related disciplinary disparities, and relying on punitive responses that undermine the very trust the system depends on. Only seven of the 45 states with threat assessment policies require schools to collect and report data on how those programs are actually working, which makes it hard to know at scale which districts are doing this well.
For a parent or educator, the practical questions are whether the school has a trained team, who serves on it, what training they have received, what the process looks like when a report comes in, and whether outcomes are tracked.
Anonymous Reporting Systems
Threat assessment teams can only work on information they receive, which is why anonymous tip lines have become a critical companion to those teams. Students are often the first to see warning signs, and they will not always walk into a principal’s office. Two systems have the strongest track record.
Colorado’s Safe2Tell is a 24/7 statewide tool that received nearly 20,000 tips during the 2018–2019 school year. Analysts at the Colorado Information Analysis Center evaluate tips and route them to schools and law enforcement, and the system has a built-in accountability feature so that every tip has to receive a response before a case can be closed.
Sandy Hook Promise’s Say Something Anonymous Reporting System serves more than five million students in grades six through twelve across 23 states. A study published in Pediatrics in January 2024, analyzing over 18,000 tips submitted between 2019 and 2023, found that 10 percent of tips involved firearms, and half of those firearm-related tips required an urgent response. The system helped prevent six planned school shootings, 38 other acts of school violence, and more than 100 planned suicides during that period. The Sandy Hook Crisis Center provides 24/7 triage with an average response time of under one minute. Overall, Sandy Hook Promise reports its programs have reached more than 50 million participants and its reporting system has received over 403,000 tips.
A tip line is only useful if students know it exists, trust it, and believe someone will act on what they report. That last piece is the one adults tend to underestimate. Students who watch a report vanish into nothing learn quickly not to bother the next time.
Keeping Firearms Out of the Shooter’s Hands
One statistic recurs across nearly every analysis of school shootings: roughly 76 to 80 percent of school shooters under 18 obtain their weapons from their own homes or the homes of relatives or friends. Prevention that ignores where the gun comes from is prevention with a hole in the middle of it.
Child Access Prevention Laws
As of January 2025, 35 states and the District of Columbia have enacted child access prevention laws, which allow prosecutors to charge adults who intentionally or negligently allow minors unsupervised access to firearms. Twenty-six of those states have stronger “negligent storage” statutes, under which an adult can be charged even if no injury occurs. Nine have weaker “reckless provision” laws that require intentional or knowing transfer. There is no federal law requiring safe storage, though a 2005 law mandates that licensed dealers provide a secure safety device with every handgun sold.
The research base for these laws is growing. RAND’s systematic review found supportive evidence that child access prevention laws reduce youth firearm suicides and unintentional injuries and deaths. One analysis found rates of unintentional child shootings are 78 percent lower in states with secure storage laws than in states without them, and studies suggest safe storage practices could reduce youth firearm fatalities by up to 32 percent. Yet more than half of all gun owners, and 55 percent of those with children in the home, report not storing firearms safely. An estimated 4.6 million children live in homes with unlocked and loaded guns.
What secure storage means in practice is straightforward: firearms unloaded, locked in a safe or with a cable or trigger lock, ammunition stored separately, and combinations or keys kept away from minors.
Parental Accountability
Prosecutors have started charging parents when negligent storage enables a child’s attack, and juries have started convicting. The prosecution of James and Jennifer Crumbley was the first time in American history that parents were criminally charged and convicted for their child’s school shooting. Their son Ethan killed four students and wounded seven others at Oxford High School in Michigan on November 30, 2021. Prosecutors showed the parents had purchased the gun for their son days before the attack and failed to secure it, even after being called to school that morning about his violent drawings. Both parents were convicted of involuntary manslaughter in early 2024 and sentenced to 10 to 15 years in prison.
Michigan responded legislatively. A suite of new gun laws took effect in February 2024, including a safe storage mandate, universal background checks, and a red flag law. Failing to store firearms safely when minors are present now carries a 15-year felony if a child uses the weapon to kill.
The pattern repeated after the September 2024 shooting at Apalachee High School in Winder, Georgia, where 14-year-old Colt Gray allegedly killed two students and two teachers. His father, Colin Gray, was charged with second-degree murder, involuntary manslaughter, and cruelty to children. Prosecutors argued he had given his son a semiautomatic rifle as a Christmas gift despite awareness of his deteriorating mental health and interest in past school shooters. On March 3, 2026, a jury convicted Colin Gray on all counts after deliberating less than two hours.
In Wisconsin, the father of the 15-year-old who carried out the December 2024 shooting at Abundant Life Christian School in Madison faces charges of contributing to the delinquency of a minor and giving a dangerous weapon to a minor. Investigators found he had given his daughter the combination to his gun safe. A judge denied his motion to dismiss in May 2026, rejecting a Second Amendment challenge and ruling that Wisconsin’s statute restricting minors’ unsupervised access to firearms is constitutional.
Red Flag Laws
Extreme risk protection order laws, commonly called red flag laws, let law enforcement, family members, and in some states educators or medical professionals petition a court to temporarily remove firearms from someone in crisis. As of January 2025, 22 states and the District of Columbia have enacted such laws. The 2022 Bipartisan Safer Communities Act provided $750 million to support state and local implementation.
The process runs through judicial review. A petitioner presents evidence that an individual poses a serious risk to themselves or others; if a judge agrees, the person is temporarily prohibited from possessing firearms. Most states allow emergency ex parte orders, issued before the subject has a hearing, for time-sensitive cases. Final orders typically last up to one year, with the subject able to request an earlier hearing.
A review of more than 6,600 petitions across six states found 77 percent of hearings resulted in an order being extended, and about 10 percent of cases involved threats to kill three or more people. The strongest evidence base is for suicide prevention. A multistate study estimated one suicide was averted for every 17 orders issued, saving an estimated 269 lives, and Indiana saw a 7.5 percent reduction in firearm suicide rates in the decade after enactment. RAND’s review found the evidence for how these laws specifically affect mass shootings to be inconclusive, in part because mass shootings are statistically rare and hard to study.
Several states — including California, Colorado, Hawaii, Massachusetts, and New York — specifically allow school personnel to file petitions, which gives educators a direct legal tool when they encounter a student or family member showing warning signs.
Mental Health Staffing
Nearly every prevention strategy depends, at some point, on a trained adult being available to a student in crisis. That is what makes the chronic shortage of school mental health professionals a structural weakness in the entire framework.
The American School Counselor Association recommends 250 students per counselor. As of the 2024–2025 school year, the national average stood at 372 to 1, an improvement from 408 to 1 two years earlier. High schools have reached the recommended ratio for the first time, but elementary and middle schools lag far behind, with ratios ranging from 571 to 694 students per counselor. The picture is worse for school psychologists: Everytown reports a national average of 1,233 students per psychologist, and a 2021 analysis found that nearly 40 percent of districts did not employ a single one.
Recent federal money made a measurable difference. Under the Bipartisan Safer Communities Act, the Departments of Health and Human Services and Education awarded $1.5 billion in grants for school-based mental health infrastructure, aiming to place 14,000 new mental health professionals in schools over five years. By early 2024, preliminary data showed school social workers up 48 percent, school nurses up 42 percent, and counselors and psychologists up 10 percent compared to pre-pandemic levels.
That funding is now in doubt. In April 2025, the Trump administration announced it would discontinue approximately $1 billion in BSCA-funded mental health grants, affecting about 260 recipients across 49 states. The Department of Education stated the grants reflected the “prior Administration’s priorities” and cited concerns that some recipients had used funds for “race-based actions.” In Corbett, Oregon, a district that had used the money to hire five new social workers learned it would have to return to just two counselors. SUNY Binghamton faced losing 10 full-time staff serving 9,000 rural students. In July 2025, New York Attorney General Letitia James and a coalition of 15 other state attorneys general filed a lawsuit seeking to reinstate the funding. Some states have moved to fill the gap: Pennsylvania announced $160 million for school safety and mental health in 2025–2026, a 107 percent increase in violence intervention funding under Governor Shapiro. The patchwork means access to a school counselor depends heavily on where a student lives.
The Federal Framework
The Bipartisan Safer Communities Act, signed in June 2022 after the Uvalde elementary school massacre, is the most significant piece of federal gun safety legislation in nearly three decades. Beyond the mental health grants above, it funded the prevention infrastructure schools rely on: the Department of Justice distributed over $73 million through the STOP School Violence grant program, which funded the creation or enhancement of threat assessment teams in more than 5,800 schools. An additional $40 million went to the COPS School Violence Prevention Program, and over $238 million supported state crisis intervention programs, including red flag law implementation.
The law also extended existing domestic violence firearm restrictions to dating partners — the so-called boyfriend loophole provision — and created the first federal criminal offenses for straw purchasing and illegal firearms trafficking. These aren’t school-shooting programs in a narrow sense, but they shape the environment in which the more direct interventions operate.
Physical Design and Emergency Response
Building design gets less attention than metal detectors and armed guards, but the evidence for it is actually better. Crime Prevention Through Environmental Design, or CPTED, applies principles like maximizing natural surveillance through open sight lines and interior windows, controlling access through vestibules and limited entry points, maintaining clear exit paths, and ensuring classroom doors can be locked from the inside without stepping into a hallway. A CDC-funded study of 50 middle schools found higher CPTED scores were associated with increased perceptions of safety, lower perceived risk, and reduced absenteeism related to safety concerns. Ohio has incorporated a CPTED checklist into its school design manual, requiring features like outward-opening recessed classroom doors and main offices positioned adjacent to primary entrances.
Panic alarm legislation has also gained bipartisan traction. Alyssa’s Law, named after a victim of the 2018 Parkland shooting, mandates silent panic alarms in schools and has been enacted in 10 states, including Florida, New York, Texas, and Georgia. The law is designed to shorten emergency response times rather than prevent attacks outright, and legislative efforts are underway in at least 14 additional states.
What the Evidence Does Not Support as a Primary Strategy
Several of the most visible responses to school shootings do not hold up well as prevention. They come up so often in school board meetings and legislative debates that they deserve a clear-eyed accounting.
School Resource Officers
Police officers stationed in schools, known as school resource officers, are one of the most politically popular responses to school shootings. The share of public schools employing them rose from 1 percent in 1975 to 44 percent by 2024. But the research on whether they prevent shootings is thin. A Congressional Research Service review found no publicly available research evaluating whether SROs deter school shootings or reduce casualties when they occur. A Washington Post examination of 197 school gun violence incidents between 1999 and 2018 identified only one case where an SRO stopped an active shooter by returning fire. At least 68 of the schools studied employed an SRO or security guard, including four of the five deadliest attacks.
More rigorous studies paint a mixed picture. Research using national data found schools with SROs experienced 30 percent fewer non-firearm-related violent incidents like fights and threats, but also a 150-percent increase in reported firearm offenses, which researchers interpret as higher detection rather than more incidents. SRO presence is also associated with more suspensions, more student arrests for low-level offenses, and no measurable improvement in students’ perceptions of safety. Iowa State University researchers found schools using officers primarily for discipline and crime response reported 91 percent more nonserious crime incidents, raising school-to-prison pipeline concerns.
Arming Teachers
At least 29 states allow some form of armed staff in K-12 schools beyond trained security guards, with implementation varying widely. RAND’s systematic review found that no studies met its inclusion criteria for any of eight measured outcomes, including defensive gun use, mass shootings, and unintentional injuries. The low base rate of school shootings and the lack of comprehensive data on which districts arm staff make evaluation extremely difficult. The National Education Association, the American Federation of Teachers, and numerous law enforcement officials cite risks of negligent discharge, the possibility police could mistake an armed teacher for a shooter, and the burden of expecting educators to use lethal force against current or former students, who make up 75 percent of school shooters. A 2022 survey found that only one in five teachers believes arming staff makes schools safer, while more than half believe it makes them less safe.
Metal Detectors
Metal detectors have proven difficult to implement reliably. In Colorado, the 27J school district suspended high school scanner trials after the technology “failed to deliver reliable alerts,” and Jeffco Public Schools found them “operationally difficult” compared to mental health supports. A 2025 University of Colorado Boulder study noted that research on entryway metal detectors “remains limited,” and the National Association of School Psychologists has warned that “extreme physical security measures can make students feel less safe.”
Aggressive Active Shooter Drills
More than 95 percent of American K–12 schools conduct active shooter drills, and at least 40 states require them. Standard lockdown drills — staying quiet, locking doors, turning off lights — are one thing. Some schools have adopted far more intense simulations involving masked “gunmen,” simulated gunfire, and in at least one documented case in Indiana, teachers being lined up and shot with pellets.
A study by Everytown and the Georgia Institute of Technology found that in the 90 days following a drill, school communities showed a 42 percent increase in stress and anxiety on social media, a 39 percent increase in depression-related language, and a 23 percent increase in physical health concerns. Nearly a third of surveyed principals and teachers reported awareness of students experiencing heightened anxiety or trauma after a drill. A RAND report found only about half of schools notify students or parents in advance, only 16 percent offer an opt-out for all students, and only about a third provide mental health resources or counseling afterward.
The American Federation of Teachers, the National Education Association, and Everytown do not recommend active shooter drills for students. If schools insist on conducting them, these organizations advise advance notice, no simulation of an actual shooting, age-appropriate content, and trauma-informed mental health support.
AI Social Media Monitoring
Schools are increasingly turning to digital surveillance tools that use AI to scan student communications and social media for potential threats. A July 2025 UC San Diego study identified 14 companies marketing these services to middle and high schools. Among them, 86 percent monitor students around the clock regardless of school hours, 71 percent use artificial intelligence to flag concerning activity, and 29 percent generate student “risk scores” based on online behavior.
The Brennan Center for Justice has characterized these tools as “experimental” and noted they have “not been proven to be valuable in preventing incidents of harm.” Researchers have flagged concerns about algorithmic bias, disproportionate targeting of minority students, and lack of transparency around how flagging algorithms work. It is also unclear whether data collected by third-party monitoring services is protected under federal student privacy law. Experts generally recommend that any digital monitoring be embedded within a broader prevention strategy rather than treated as a standalone solution.
Putting the Layers Together
The recurring lesson from the research and from the record of past attacks is that no single intervention is sufficient. Effective prevention requires a school climate where students trust adults enough to report concerns, trained threat assessment teams ready to act on those reports, anonymous tip lines that lower the barrier to reporting, mental health professionals available to intervene, laws that keep firearms out of the hands of minors, red flag orders when someone is in crisis, and parents who store their weapons securely. Physical security and emergency protocols work best as the last line behind a system built to identify and address threats long before anyone reaches for a weapon.
For parents and educators, the practical questions are the same ones that fall out of that list. Does the school have a functioning threat assessment team? Is there a working anonymous tip line, and do students know about it? What is the counselor-to-student ratio? Does the state have child access prevention and red flag laws, and do school personnel know how to use them? Are firearms in the home locked, unloaded, and separated from ammunition? These are the levers that show up over and over in the disrupted plots and the postmortems of the ones that were not.