Greene-Colozzi separates routine lockdown drills from active shooter simulations

Pediatricians recommend neutral terms for drills with young children

Emily Greene-Colozzi’s commentary, originally published by The Conversation and republished by United Press International on Sept. 16, 2026, draws on federal statistics, state-by-state drill requirements and academic studies to argue that two school preparedness exercises routinely discussed as if they were interchangeable are, in her account, distinct in form, prevalence and the research base supporting them.

Greene-Colozzi describes the simpler of the two — the lockdown drill — as built around what she calls “locks, lights and moving out of sight.” Teachers and students lock classroom doors, turn off the lights and move to an area without sight lines until an all-clear is given. Carrying out the routine, she writes, “can build familiarity and muscle memory that encourage a rapid and calm response in the event of an actual emergency.” Lockdowns may be initiated for reasons unrelated to an armed assailant, she notes: a student once told her the single lockdown the student experienced in elementary school was in response to a squirrel that had invaded the building. Other schools have implemented lockdowns for graver threats: parent disputes that become physical, nearby police activity, wildlife, or, in the worst-case scenario, an armed assailant.

The other practice is the active shooter simulation, which Greene-Colozzi says is specific to armed assailants and may include actors posing as shooters, mock gunfire, fake blood and the use of nonlethal projectiles such as BB guns or paintball guns. She notes that high-intensity simulations are restricted in some states, including New York and California, that other states may explicitly differentiate between active shooter simulations and lockdown drills, and that many states have no guidelines at all related to simulations in schools.

A survey of K-12 teachers cited by Greene-Colozzi found that 55% reported active shooter drills in their schools did not include sensory elements such as fake blood, around 6% had experienced drills with simulated gunfire, and 1% reported fake blood or explosions. Greene-Colozzi writes that these figures show how uncommon the most extreme simulations are — and how they nonetheless tend to generate the most media attention and public outcry.

Both practices exist within a legal landscape that has shifted since the 1999 mass shooting at Columbine High School in Jefferson County, Colorado, after which various kinds of preparedness drills became mandatory in most schools. As of 2025, Greene-Colozzi reports, 37 of 50 states require schools to conduct active shooter or lockdown drills at least once per year. New York requires lockdown drills at various points throughout the year. Texas requires lockdowns and shelter-in-place drills and also permits active shooter threat exercises, including shooter simulations.

A key conflation, Greene-Colozzi argues, is in how the prevalence of each practice is reported at the federal level. When federal sources report that 95% of U.S. schools implement lockdown drills, the figure “mostly refers to locks, lights and out-of-sight practice — not simulations and armed assailant drills,” she writes. A National Academies of Sciences, Engineering, and Medicine report on the mental and emotional risks of active shooter drills cited the same 2023 statistic but, in Greene-Colozzi’s reading, presented it ambiguously as reflecting “active shooter drills” rather than lockdowns. The National Academies report “found mixed results on the impact of active shooter drills” and “revealed a lack of standardization across schools for drills and preparedness in general,” she writes — a gap that has, in her account, “made it nearly impossible to understand what is harmful, what is helpful, and what should be common practice.”

Greene-Colozzi also points to a research gap on simulations. Studies show “significant concerns about the psychological harm these simulations can have on students and teachers,” she writes, but “there are no existing studies that test whether they improve outcomes in real-world active shooter scenarios, because the baseline rate of these attacks is so low.” Yet these drills, she argues, tend to generate the most media attention and public outcry and are conflated with lockdown drills, leading parents hearing about lockdown practices to draw parallels to “terrifying simulations with pretend shooters and gunfire.”

The research that does exist on lockdowns is more encouraging. Greene-Colozzi cites studies of middle and high school students in a large urban central New York school district who reported lower fear and better preparedness after participating in lockdown drills using the locks-lights-out-of-sight approach. Observational research she cites “suggests that lockdowns can impede shooters’ movement through space, potentially mitigating harm.” Research from Texas State University has found that unsecured doors were associated with more victims during active shooter incidents at schools, and a separate study suggested lockdowns are associated with fewer casualties during mass school shootings. Greene-Colozzi also notes that other studies, assessing various exercises ranging from lockdowns to active shooter simulations, report mixed and negative impacts on fear and anxiety. The body of research on preparedness drills, she writes, “lacks the nuance required to establish clear harm or benefit to practicing for an active shooter situation.”

Professional organizations, Greene-Colozzi writes, warn that high-intensity active shooter simulation drills may cause trauma for students without making them more prepared for such a terrifying, real-life situation. There is, she says, “cautious consensus among experts that some kind of intruder preparedness is necessary.” The question, in her framing, is how that preparedness is practiced. “When conducted with the procedural simplicity of fire drills,” she writes, lockdowns “may be the least traumatic and most effective drills.” She adds: “Just as fire drills rarely simulate actual fires, lockdown drills need not introduce harmful or deceptive scenarios that explicitly recreate an emergency.” With a lack of standardized practice, guidelines and terminology, “disentangling the distinct outcomes and effects of lockdowns from the consequences of ambiguously defined ‘active shooter drills’ is an uphill battle.”

For young children, Greene-Colozzi argues, the routine can be learned without the rationale. At the start of the 2026-27 school year, a parent posting on the subreddit “Daddit” shared a story about his preschool-aged child practicing staying quiet so “the bad guy” would not hear her — a scenario she calls “simply not needed” at that age. “In early childhood and beginning elementary school, the routine can be learned without the rationale or explanation,” Greene-Colozzi writes. As children age into middle and high school, lockdown practice is paired with the rationale, “incorporating more sophisticated discussions about school safety, violence prevention and response, and emergency preparedness.”

Greene-Colozzi adds a first-person example from her own household: her preschooler has informed her of “quiet times” when he and his classmates sit in a corner and learn to stay quiet. When prodded for more explanation, the child offered no reasoning beyond the practice being “a time to be still and quiet.”

The American Academy of Pediatrics, Greene-Colozzi writes, advises that adults running these drills use neutral phrases such as “lockdown” or “safety drill,” rather than a more frightening term like “active shooter drill.” Some schools follow this guidance; others may not, she reports.

Greene-Colozzi is an assistant professor of criminology and justice studies at UMass Lowell. Her article was originally published by The Conversation under a Creative Commons license.