The topic of school policing remains difficult and contested—from viral videos of police and student encounters gone wrong, to a seeming surge in violence that’s causing some districts to consider adding more cops in schools, to perennial fears about school shootings.
Our explainer outlines the definition of school resource officers, how they differ from other police and school safety personnel in schools, research on their effectiveness, and some of the difficult tradeoffs district officials and others must contend with as they examine their school policing programs.
What is a school resource officer? Are SROs armed?
A school resource officer is a sworn law-enforcement officer with arrest powers who works, either full or part time, in a school setting. Nearly all SROs are armed (about 91 percent, according to federal data), and most carry other restraints like handcuffs as well.
What does school resource officer training look like?
The main difference separating an SRO from other police officers is that, in theory, they have had some special training on how to work with youths. A membership group for SROs, the National Association of School Resource Officers, offers several such courses. NASRO’s basic 40-hour training includes some content on the adolescent brain, cyber safety, and violence prevention in schools, among other topics.
In practice, it’s not clear how many school police actually have had this training or similar types. States set different requirements for what training SROs need to have before working in schools, and some SROs report feeling unprepared for the job. In a 2018 Education Week Research Survey of SROs, about 1 in 5 respondents said they didn’t have sufficient training to work in a school environment, only 39 percent said they had training on child trauma, and about half said they hadn’t been trained to work with special education students.
What do school resource officers do?
As for daily duties, NASRO indicates that officers play a tripartite role of law enforcement, informal mentoring and counseling, and some in-person teaching. In this sense, the theory of school-based policing is aligned with that of community policing: using local partnerships with other public entities to bring more resources to bear on safety.
Similar to the debate about whether community policing truly improves trust in law enforcement and safety—or merely increases surveillance—critics question whether it’s possible for the same officers to play all those roles at once.
A recent NASRO survey underscores this potential tension. It found that two-thirds of SROs responding said they most identified with law enforcement, and just over a quarter most identified with being a mentor. (These findings are generally consistent with prior research on school police officers’ own perception of their roles.) Yet the officers also reported that they spent the greatest amount of their time—48 percent of it—on mentoring activities.
School resource officer statistics: How many SROs are there?
SROs are not required to register in any kind of national database, so there are only estimates of their numbers—no firm tally.
Federal data estimate that in the 2015-16 school year, there were some 52,000 full or part-time SROs in schools at least once a week, plus another 15,500 sworn law enforcement officers in schools who were not SROs.
Another way to examine this picture is to look at the proportion of schools that employ an SRO.
The most recent federal data available, from the 2017-18 school year, show that about 45 percent of schools had an SRO in place at least once a week. (Another 13 percent of schools reported hosting police who were not SROs.)
This represents a steady growth over the last few decades; only 32 percent of schools reported having an SRO in 2005-06.
As these data suggest, an SRO may not be stationed in just one school; some are responsible for several campuses. The Maryland Center for School Safety found, for instance, that there were 439 SROs serving schools in that state as of 2020, but only 328 were assigned to just one school.
Why has the number of school resource officers grown?
Although school policing has been around since at least the late 1950s, it expanded notably in the 1990s due to three major factors: concerns about rising rates of juvenile crime in the 1990s, the federal government’s funding of community policing programs beginning with the 1994 crime bill and its establishment of the Community Oriented Policing Services (COPS) hiring program, and the 1999 Columbine shooting in Littleton, Colo.
In 1999, the U.S. Department of Justice began specifically making grants to increase the number of SROs in schools through the COPS in Schools program, resulting by some estimates more than $700 million being granted to districts to hire SROs between 1999 and 2005. That grant has ended but districts can still receive federal grants through the broader COPS funding.
Traditionally, SROs have been more common in secondary schools than in elementary schools, but there are indications that the proportion working in elementary schools has risen. This appears to be a relatively recent phenomenon caused by several high-profile school shootings in the late 2010s, as states began to pass laws requiring SROs or other armed personnel in schools.
The end result is that more districts have added SROs in lower grades. Florida saw a dramatic increase in police presence between 2017-18 and 2018-19 after passing legislation developed in response to the 2018 school shootings in Parkland, with much of that due to increases in the the elementary grades.
Besides school resource officers, are there other police officers or armed individuals who work in and around schools?
Yes. These can be campus security officers, regular beat cops who are assigned to school areas, and even laypeople.
A 2018 Maryland law, for example, requires schools to have SROs or “adequate police coverage,” which can include sheriff’s deputies, patrol officers, or others who can access school grounds in response to calls or to conduct other business.
And a Florida law passed the same year required all schools to hire either an SRO or to have an armed guardian, a layperson who carries a firearm and participates in a state training program.
Do districts get to select school resource officers?
This depends on the arrangement that school districts have with law-enforcement agencies. Some have little say in selecting the officers, while in other districts, central office administrators or even principals can interview the officers and select or reject candidates.
A handful of large districts, including Miami-Dade, Los Angeles, Dallas, and Houston, among others, have their own in-house police forces, presumably because they can more directly control hiring and train them for the nuances of their own schools, though there is little to suggest that an in-house police force yields different outcomes for safety. Other districts, including Shelby County, Tenn., are expressing new interest in these arrangements.
What is an MOU? What do they govern?
A memorandum of understanding or MOU is an interagency agreement that theoretically documents how SROs are selected and trained, prescribes their duties and limitations, details how the agreement can be renewed or modified, and specifies how costs are apportioned among the agencies.
Only about two-thirds of districts in 2017-18 reported having such a document. And even then many respondents were unsure whether theirs specified their SROs’ role in disciplinary matters, on the use of firearms, or on arrests.
Some districts, including Chicago and New York City, have recently modified these documents to clarify that SROs should not be involved in routine discipline matters (like a student interrupting or refusing to follow directions in class). New York’s also calls on them to use diversionary tactics for low-level crimes and only to arrest in the case of violent crimes or felonies.
It’s not clear how such changes might affect outcomes for students, because researchers haven’t yet attempted to analyze a large sample of MOUs or to correlate specific features of MOUs to things like student safety, behavioral incidents in schools, juvenile-justice referrals, or other outcomes.
What do we know about school resource officers and their effectiveness on schools from research?
Studying SROs is a difficult task. They usually aren’t managed by schools, but by police departments, which makes it difficult to track which schools have officers. Until this decade, cause-and-effect research on SROs was virtually nonexistent, despite the millions of dollars spent hiring, training, and placing them in schools.
Now that’s starting to change. Newer studies have used complex statistical methods to link the presence of SROs to both student behavior patterns and their consequences. The emerging picture suggests that while school police do mitigate some types of violence in schools, their presence also increases certain kinds of disciplinary outcomes, including suspensions and expulsions, as well as arrests. (See the next header for details.)
Despite these advances, many holes remain in the research. For one thing, even the best empirical studies don’t offer a lot of insight into what happens in the black box of school culture. Principals, for example, are the ones who ultimately make decisions about school discipline and suspensions, suggesting some of these patterns are not merely due to police officers’ presence but because educators are asking them to intervene. The findings point, in other words, to a larger problem of the cultural context of schools. (In its own survey of SROs, for example, NASRO officers reported that more than a third of arrests they made were referred to them by school staff.)
We also know less about how other differences in SRO characteristics shape school policing. For example, how does an SRO’s age, experience, type or intensity of training, or other factor influence how they work with principals, teachers, and educators?
Case studies, observations and interviews of SROs paint a more qualitative picture of SROs’ beliefs and attitudes about their roles. These tend to be based on non-nationally representative samples, though, which could introduce bias into the results.
Some advocates, including Black Lives Matter activists, argue that school resource officers contribute to a ‘school to prison pipeline.’ Why?
Analyses of federal education data by the EdWeek Research Center and other news organizations have detailed large, persistent disparities in arrests at schools by student race.
Education Week found, for instance, that in 43 states and the District of Columbia, Black students were arrested at school at disproportionately high levels—sometimes at shockingly high rates. In 10 states, it found that the share of arrested Black students was 20 percentage points higher than these students’ share of enrollment. (These figures were most disproportionate for Black students, but, to a lesser extent, also show up for other students of color.)
Such patterns have long been highlighted by civil rights advocates as a product of systemic racism in schools. Those advocates have also pointed to larger structural problems affecting Black students including higher suspension and disciplinary rates, as well as to reduced access to quality teachers and advanced coursetaking.
Research on implicit bias shows that, for example, Black boys and girls as young as 10 are viewed as older, more worldly, and more likely to be perceived as guilty by police than other students. Thus advocates for Black students argue that the police presence tends to subject these students to harsher discipline and to funnel more of them into the penal system.
While suggestive, these data weren’t conclusive evidence that police in schools were directly responsible for these patterns; perhaps SROs were simply more likely to work in schools with more problems.
But now a growing body of new empirical research shows a consistent link between the presence of police officers in schools and these discipline patterns. Most of this research is based on analyses of districts that have participated in the COPS grant program. Researchers have found ways to compare discipline outcomes between schools in districts that received the grants to those that didn’t, while controlling for demographics. Some of these analyses focus on student-level outcomes.
In one study released just this year, for example, researchers found that the presence of SROs in schools that received those grants saw a higher proportion number of suspensions, expulsions, police referrals, and arrests of students compared to those that missed out on the grants; the effects were two times larger for Black than for white students. This study inches closer to a cause-and-effect model than most prior research.
It’s consistent with some other recent studies, one of which found that adding police led to more arrests among children under age 15 as a result of the grants. A study in Texas, found that middle school disciplinary rates rose by 6 percent after schools received the grants and that the increases were concentrated among Black and Hispanic students.
Recent research based on structured interviews with several dozen SROs have found that race was a key factor in their perception of threatening behavior. Those working in an urban, diverse district tended to see students themselves as the greatest threat to safety, citing fights, bullying, and aggression, while those working in a suburban, majority white district tended to view intruders from outside the school as the greatest threat to safety.
Do school resource officers help make schools safer?
In a sense, the answer to this question truly depends on how communities defines a “safe school.” Is a safe school one that has few or no violent incidents? One replete with bulletproof glass and metal detectors? One that values strong, warm relationships among faculty and students? Opinions differ, school communities prioritize different ideas about safety, and not all of the different notions are easily compatible.
That said, by at least one definition, they do appear to make a difference in one dimension of safety. A series of recent studies conclude that the presence of SROs does appear to lead to declines in violent incidents in schools, such as rape, robbery, and physical attacks.
On the other hand, it is far from clear that SROs do much to prevent school shootings—the very phenomenon that prompted a large increase in their numbers in the past decade.
In fact, one recent study found some preliminary though not conclusive evidence that the presence of SROs increased, rather than decreased, the odds of firearm-related incidents on campuses. This could be because having SROs, by definition, increases the number of guns at school. (The researchers urge caution about the finding because the number of school shootings in the sample was so small.)
These safety improvements seem to come at a significant cost for some students, as discussed in the previous section.
Have any districts taken steps to remove school resource officers?
Yes. EdWeek maintains a database, which we periodically update, of districts that have either cut funding to their school police programs or removed SROs from buildings.
Even in those cases, though, police may be called in the case of a violent incident or may work with schools in other arrangements.
How are we supposed to interpret these findings overall?
That’s the huge challenge facing school district leaders, school boards, and principals.
One way is to consider whether the safety benefits of SROs still justify the cost, given the documented harms of exclusionary discipline, suspensions, and juvenile justice referrals. In general, violence and crime rates in schools have declined over the past 20 years, raising questions about salience: Is it still necessary to have so many police officers in schools?
High profile school shootings, including Sandy Hook, Conn., in 2014 and Parkland, Fla. in 2018 have complicated the discussion—though there’s little to suggest that the presence or absence of school police might have prevented these.
Thus the larger question seems to be sociological. Uniformed officers and panda cars, along with metal detectors and bulletproof glass, are powerful signifiers for parents and community members that something’s being done to address safety regardless of whether they actually make students safer.
And there remains much uncertainty—as well as considerable doubt from advocates—about whether tweaks, including better-written MOUs and more district control over SRO programs can fundamentally reshape the school policing conversation.
Many research studies and white papers examine the role and impact of school resource officers. Here are some of the most important to get you started.
Fisher, Benjamin W., Ethan M. Higgins, Aaron Kupchik, Samantha Viano, F. Chris Curran, Suzanne Overtreet, Bryant Plumlee, Brandon Coffey. “Protecting the Flock or Policing the Sheep? Differences in School Resource Officers’ Perceptions of Threats by School Racial Composition.” (2020). Social Problems, 00, 1-19.
Meister, Craig, and Jeyan Jebari, “Annual School Resource officers/Adequate Coverage Report.” (2020). Maryland Center for School Safety.
Mielke, Frank J., Jeremy Phillips, and Beth Sanborn. Measuring the Strategic Fit of the School Resource Officer with Law Enforcement Leaders, the Education System, the Community and Other Interested Parties. (2021). National Association of School Resource Officers.
Musu-Gillette, L., Zhang, A., Wang, K., Zhang, J., Kemp, J., Diliberti, M., and Oudekerk, B.A. (2018). “Indicators of School Crime and Safety: 2017" (NCES 2018-036/NCJ 251413). National Center for Education Statistics, U.S. Department of Education, and Bureau of Justice Statistics, Office of Justice Programs, U.S. Department of Justice. Washington, DC.
Na, C. & Gottfredson, D. C. “Police Officers in Schools: Effects on School Crime and the Processing of Offending Behaviors.” (2011). Justice Quarterly, 30(4), 1-32.
Sorensen, Lucy C., Yinzhi Shen, and Shawn D. Bushway. “Making Schools Safer and/or Escalating Disciplinary Response: A Study of Police Officers in North Carolina Schools.” (2021). Educational Evaluation and Policy Analysis.
Petrosino, Anthony, Trevor Fronius, and Darius Taylor. “Research in Brief: School-Based Law Enforcement.” (2021). WestEd Justice & Prevention Research Center.
Sorensen, Lucy C., Montserrat Avila Acosta, John Engberg, and Shawn D. Bushway. The Thin Blue Line in Schools: New Evidence on School-Based Policing Across the U.S. (2021). Annenberg Institute at Brown University.
Stern, Alexis, and Anthony Petrosino. “What Do we Know About the Effects of School-Based Law Enforcement on School Safety?” (2018). WestEd Justice & Prevention Center.
Weisburst, Emily K. Patrolling Public Schools: The Impact of Funding for School Police on Student Discipline and Long-term Education Outcomes. (2019). Journal of Policy Analysis and Management.
A version of this article appeared in the December 01, 2021 edition of Education Week as School Resource Officers Explained