Summer’s arrival ended for now the anti-war protests that rocked college campuses across the U.S. during the spring 2024 semester. Israel’s assault on Gaza, however, grinds on, and student protests may erupt again in the fall, especially as the presidential election heightens political tensions.

Once again, university presidents across the U.S. may be forced to make difficult and controversial decisions: Should they tolerate youthful civil disobedience, quash dissent or seek peaceful resolutions?

My research on civil disobedience, deliberation and democracy offers a way to parse this important question.

Threatening or peaceful protest?

Between November 2023 and May 2024, thousands of students on more than 120 university and college campuses across the country established encampments to protest Israel’s war on Hamas in Gaza. They also decried what they saw as support for that war through their universities’ investments and other connections to Israel.

At some campuses, including Columbia, UC Irvine, and Portland State University, students took over buildings and sometimes vandalized facilities, prompting widespread condemnation.

Most student encampments, however, were peaceful and nonviolent. The Crowd Counting Consortium, a Harvard Kennedy School project that collects data on protests worldwide, reports that protesters damaged property on just 10 campuses. Nonetheless, police arrested protesters at 60 schools. Those university presidents who asked either campus police or local police departments to intervene said they had to protect community members from violence and safeguard teaching, learning and research.

Yet half of all campus anti-war protests disbanded without any arrests. At Brown, Northwestern, Rutgers, Johns Hopkins University and others, university presidents pursued de-escalation, negotiation and other peaceful paths to resolving conflict. After administrators agreed to measures such as transparency on investments, support for Palestinian students and scholars, or reducing sanctions for protesters, students voluntarily removed their tents and left to study for finals.

So when, if ever, should universities deploy police against student protests?

‘Ladder of harm’

The answer depends on how disruptive protests are.

Here is a scale to assess some levels of harm. It builds upon recommendations developed by University of California lawyers Chris Edley and Charles Robinson following a bout of aggressive police action against protesters at UC Davis in 2011.

The ladder of protest harms runs from level 1 – civil disobedience without disruption – to level 4, indicating a violent protest presenting imminent danger to public safety. It provides a shared standard for those who, while disagreeing about whether student protesters are right or wrong, righteous or hateful, can use it to collectively assess the extent of the harm and disruption their protests cause.

People tend to disagree on this matter. During the spring 2024 anti-war uprising on Harvard’s campus, for example, students and faculty voiced starkly different opinions about how disruptive it was.

“They have set up forty tents, draped the iconic John Harvard statue with a keffiyeh, pounded music through a loudspeaker, raised Palestinian flags over University Hall, and chanted over bullhorns,” professors Jeff Flier and Steven Pinker wrote in The Boston Globe. Their comments suggest they saw the Harvard encampment as intolerably disruptive – a level 3 on a scale of 1 to 4.

Many students, however, found the occupation of Harvard Yard unobtrusive – more like a level 1.

The Harvard Crimson interviewed 40 freshmen who lived very near the encampment on campus. “Nearly all said the encampment has not significantly changed their daily lives or prevented them from studying,” the paper reported. One student with “a view of the encampment from her dorm” compared the noise level with that of tourists milling about the Yard.

Faculty, administrators and students at other schools also held markedly diverging assessments about their Gaza encampments.

After armed police at Emory University used chemical agents and electric shocks to clear protesters, ultimately arresting at least 28 people, university President Gregory Fenves wrote in a letter that “we will not tolerate vandalism, violence, or any attempt to disrupt our campus.”

Soon after, the faculty overwhelmingly voted “no confidence” in Fenves, calling the encampment a “peaceful demonstration” with “no evidence of violence” and “no disruption of teaching and research activities.”

People also disagreed on what threshold of disruption warrants police action.

Some administrators felt that any violation of university rules justified police response, even a level 1 tent encampment that didn’t block access to offices or classrooms or make much noise. Dartmouth College President Sian Leah Beilock, for example, asked police to clear protesters just two hours after they set up tents in violation of campus rules against erecting structures.

Certainly, that’s the standard at many private companies. If employees at Meta pitched protest tents on their campus, few would be either surprised or dismayed if the police came immediately and cleared them out.

Yet Harvard Police Chief Victor Clay set the bar for arrest much higher – at around level 4. He told the Crimson in April 2024 that only “significant property damage or physical violence at any level” would warrant detaining students. The Baltimore Police Department was similarly reluctant to move in on what it called the “valid” encampment at Johns Hopkins University.

Leadership at both universities ultimately resolved their encampments without law enforcement.

Using the scale

The ladder of harm cannot settle disagreements about whether students are right or wrong. It cannot even fully resolve subjective opinions about how harmful their protests are. But it may help move beyond the simplistic and often mistaken judgments that characterized much discussion of campus protests in spring 2024.

One side proclaimed: Students broke the rules; call the police. Others condemned any use of force against protesters.

In many cases, people demanding police involvement didn’t like the protesters’ criticisms of Israel. Many university presidents felt enormous pressure from university board members, Congress, alumni and advocates to quell the protests.

On the ladder of harm, none of these justify calling the police.

The threshold for forcibly terminating deliberation at educational institutions is high for good reason. Reason and discussion as methods of resolving disagreement are central to the DNA of universities and colleges in a way that is not true of corporations or government agencies.

Civil disobedience, by design, is in part persuasive and in part disruptive. Police action is only coercive and dialogue-ending. And arresting students has serious consequences, including expulsion, a criminal record, the loss of financial aid and perhaps reduced job prospects.

Yet police action is sometimes necessary, according to the ladder of harm. If and when protests endanger people, disrupt critical school activities or inflict other serious harms, then – and only then – it’s time to call law enforcement.

Dialogue, learning and debate in the pursuit of truth and wisdom are among the core values of a university. Flash-bang grenades, Tasers and riot shields are antithetical to those values.

Archon Fung does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.