In December 2012, a Senate subcommittee was convened to examine the school-to-prison pipeline, a national trend in which overly punitive school discipline policies push students out of school and into the criminal-justice system. Among the witnesses at the first-ever congressional hearing on this issue was Edward Ward, at the time an honor-roll student in his sophomore year at DePaul University and a recent graduate of Orr Academy on the West Side of Chicago. He offered an eye-opening first-hand account of his high-school experience. “From the moment we stepped through the doors in the morning, we were faced with metal detectors, X-ray machines, and uniformed security,” said Ward, describing a high-poverty, majority-black campus “where many young people … feel unwelcome and under siege.”

Far from an aberration, what Ward depicts—public schools serving primarily black and other nonwhite students that rely on more restrictive security—is quite common, according to a new research paper from Jason P. Nance, an associate professor of law at the University of Florida Levin College of Law. Nance set out to find if there was a proliferation of school security following highly publicized school shootings like the tragedy at Sandy Hook Elementary School in Newtown, Connecticut. He discovered that many schools had intensified their security and surveillance of students, but the practice was not equally applied. Rather, schools with a preponderance of students of color within the school building were more inclined to adopt strict surveillance practices—metal detectors, locked gates, security cameras, random sweeps, and school police.

In the first empirical analysis of its kind, Nance gained authorization to access a restricted database from the U.S. Department of Education—the School Survey on Crime and Safety conducted in 2009-10 and 2013-14—to examine school security methods pre- and post- the Newtown school massacre. He found a clear and consistent pattern, even after controlling for a host of variables that might explain the presence of stricter student surveillance, such as school crime, neighborhood crime, school disorder (disciplinary or behavioral problems on campus), and other student demographics and school characteristics.

“After controlling for all those things, I still found that the concentration of students of color was a predictor of whether or not schools decided to rely on more intense [security] measures,” said Nance, referring to black, Hispanic, Asian, and Native American children. “I questioned why that was [and] it seemed like race was playing a factor in these decisions.”

His research carefully documents the degree to which race influenced surveillance decisions. Nance used logistic regression models—a statistical method for analyzing a dataset—to predict the odds of a school using a particular combination of security options. The study suggests that as the portion of students of color in the school increased, so did the odds that the school would rely on more intense surveillance methods. In schools where students of color accounted for more than half of the student body, the probability of the school using a mix of metal detectors, school police and security guards, locked gates, and random sweeps was two to 18 times greater than at schools where the nonwhite population was less than 20 percent. “Schools with higher concentrations of [students of color],” he concluded, “are more inclined to rely on heavy-handed measures to maintain order than other schools facing similar crime and discipline issues.”

But not all school districts see stricter security policies as a downside—even in districts serving an overwhelmingly nonwhite student body. In Boston, the chief of police for the city’s schools told MassLive.com last year that metal detectors are a deterrent to thwart weapons in schools, and he considers the addition of the security method a success story. In Boston’s three largest high schools, every student is required to walk through a metal detector every school day. “The idea now is that schools are more of a safe zone and that helps parents,” said Eric Weston, a 30-year veteran of school policing, who believes it makes students feel safer. “They know they can't bring in a weapon, but they also know the kid behind them can't either.”

The extent to which the increased security was related to race and ethnicity, rather than grounded in legitimate safety concerns, is further proven in a companion analysis in which Nance investigated the major, student-caused instances of school violence for the last 25 years using information culled from a CNN archive of U.S. school violence incidents and federal data on demographics of the relevant schools. The overwhelming majority—some 62 percent—of the occurrences of major school violence happened in schools that serve primarily white students. These findings are “illustrative of a much greater problem that we have of racial inequalities within our [public] school system,” Nance said, noting research on racial disparities in special-education placements, gifted-and-talented programs, and teacher expectations of academic success. He also acknowledged that “African Americans tend to experience [educational inequalities] to the highest degree.”

Additionally, the report emphasizes the educational and sociological harms of constant student surveillance, linking the over-reliance on strict security with students’ diminished feelings of trust and safety. One of the scholars who has studied and written extensively on this aspect is Pedro Noguera, a distinguished professor at UCLA’s graduate school of education. “When we think about what leads to safety in schools, we have to focus on how safety relates to the quality of relationships, relates to kids receiving the education they need, and not rely on excessive security,” Noguera said. “Because when we do, the impact on learning, the impact on the way kids feel about being there, and the likelihood [students] will be subject to very punitive forms of discipline goes way up.”

In New York City, Noguera cites public schools with metal detectors “where they literally can’t get the kids into the building on time because [the screening] takes so long,” and cautioned that the long-term impact can be seen in student motivation and engagement. “You want schools to be safe, but at the same time you want them to be places where kids feel as though they can learn and be supported,” Noguera said, adding that bringing police onto campus and placing youth under continuous surveillance “begins to turn schools into institutions that are more like prisons.”

The increasing reliance on strict security practices has led activists and students in some large city school districts—where these methods are most commonly found—to push back against school environments where, as Noguera writes, “the fixation on control tends to override all other educational objectives and concerns.” A districtwide policy in Los Angeles to conduct random screenings with metal detector wands in all secondary schools (grades 6-12) has been in place for over two decades, yet concerns about the rule resurfaced in June, with local groups calling for the district to change its security procedures. Similarly in New York, the nation’s largest school district faces growing calls to remove metal detectors from schools.

Kesi Foster, the New York City coordinator for Urban Youth Collaborative, a student-led educational-justice coalition, is part of the movement to reform these practices. “We have yet to see any evidence that this kind of [intensive surveillance and] policing … creates an academic environment where [students] are more likely to thrive, improves school culture and climate, or creates a safer learning environment. Yet cities, states, and the federal government continue to invest in these kind of strategies and the only results we see is the criminalization of black youth in their schools.”

Curbing the involvement of school-resource officers in minor student misbehavior recently resulted in federal guidance from the U.S. Departments of Education and Justice “emphasizing the importance of well-designed SRO programs.” However, some advocates say the issue is broader than just preparation and training.

Foster works with black and Latino youth who go to school in the Bronx and Brooklyn and says strict surveillance creates an environment where young people “understand the school system sees them always as a potential problem or threat.” He describes schools practically across the street from each other—one a selective high school with no metal detectors and few school-safety agents, the other a majority-black neighborhood high school with metal detectors and police greeting students at the front door. “The students with the metal detector understand in many ways the city sees them as less than or as criminal out the gate,” said Foster.

Echoing UCLA’s Noguera, Foster said studies show schools are safe when young people build strong, open, and positive relationships with adults in their building. “School districts should divest the money they are spending on [surveillance and policing] and reinvest that money to hire more guidance counselors and restorative justice coordinators, and train community members to … support the social and emotional growth of children.”

The research paper’s author endorses this idea. Nance says there are concrete ways for schools to create and maintain safe environments without depending on rigid security measures—including confronting subconscious attitudes and stereotypes that lead school staff to treat students of color differently. “If [these disparities] are not existing because of safety concerns, then … my research tends to suggest that implicit racial bias seems to be explaining … why we see them.”

He speaks from a theoretical and a practical perspective: Nance taught in Houston from 1996 to 1999 and observed drug-sniffing dogs, metal detectors, and police officers within a school serving mainly students of color. Conceding that most educators are “acting in good faith and…care about kids,” he still worries about the lingering effects.

“The message that we are giving to our students now is that white children have greater privacy rights than [nonwhite] children. That, to me, is fundamentally unfair. That, to me, exacerbates the racial tensions that our nation is already confronting. Why are we feeding that?”