Inside Trump’s Crackdown on Dissent: Obscure Laws, ICE Agents and Fear

For several months, President Trump has warned that he intends to deport foreign students who participated in last year’s campus protests over the Israel-Hamas conflict.

Meanwhile, his administration has been taking concrete steps to follow through.

Officials from a division of Immigration and Customs Enforcement, typically tasked with investigating human trafficking and drug smuggling, searched the internet for social media activity and videos that could be interpreted as expressing support for Hamas, according to administration sources. These investigators compiled reports on multiple protesters and forwarded them to the State Department, which invoked a little-known legal provision to justify the weekend arrest of 30-year-old lawful permanent resident Mahmoud Khalil.

Mr. Trump declared this week that Khalil’s arrest was just the first of “many to come.”

Civil rights organizations argue that the arrest of Mr. Khalil—a green card holder married to a U.S. citizen—constitutes a blatant violation of the First Amendment. However, they also see it as part of a broader strategy by Mr. Trump to use federal authority not only against lawbreakers but also to suppress dissent.

“Freedom of speech has its limits,” said Thomas D. Homan, who oversees Mr. Trump’s deportation initiative, during a meeting with New York lawmakers in Albany on Wednesday. “We consider him a national security threat.”

Despite not being charged with any crime, Mr. Khalil faces deportation under a provision of the Immigration and Nationality Act. The government claims that his involvement in the Columbia University protests harmed U.S. foreign policy interests by fostering antisemitism.

According to the statute, any “alien whose presence or activities in the United States the Secretary of State has reasonable ground to believe would have potentially serious adverse foreign policy consequences for the United States is deportable.”

As a spokesperson and negotiator for the pro-Palestinian demonstrations at Columbia, where he earned a master’s degree in December, Mr. Khalil has been unable to hold a private conversation with his legal team since his arrest, his lawyers reported on Wednesday.

Georgetown University Law Center professor Stephen Vladeck noted that there is only one other known case in which similar legal powers were invoked in deportation proceedings.

That case involved Mario Ruiz Massieu, a former deputy attorney general of Mexico who entered the U.S. on a visa in 1995. The U.S. government sought to deport him due to money laundering and other criminal charges in Mexico. Then-Secretary of State Warren Christopher justified his removal by arguing that allowing Ruiz Massieu to remain would undermine U.S. efforts to promote judicial reforms in Mexico. The case was delayed by appeals.

According to Mr. Vladeck, key differences exist between the two cases. While Ruiz Massieu was a foreign government official facing corruption charges and residing in the U.S. on a temporary visa, Mr. Khalil holds a green card, which provides a pathway to permanent residency, and engaged in what appears to be constitutionally protected speech.

“The government’s actions appear to be retaliatory against constitutionally protected, albeit controversial, speech,” Mr. Vladeck said.

Although the Trump administration claims that Mr. Khalil’s role in the Columbia protests indicates an “alignment with Hamas,” officials have not accused him of any direct ties to the organization, nor of receiving orders or providing material support to it.

Throughout his presidency, Mr. Trump has spoken openly about using executive power to exact retribution. He has fired or investigated government officials he deemed disloyal, revoked security clearances from critics, and placed federal employees promoting diversity initiatives on leave.

Critics argue that Khalil’s arrest is intended as a warning.

“We cannot allow this country to descend into a system of presidential authoritarianism, where individuals are taken from their homes, arrested, and detained simply for expressing political opinions that the president dislikes,” said Representative Jamie Raskin, a Democrat from Maryland and the ranking member of the House Judiciary Committee.

Mr. Raskin described Khalil’s detention as “a deeply alarming precedent set by an administration determined to weaponize fear and intimidation to silence opposition.”

Legal scholars warn that Mr. Trump’s actions could have a chilling effect on free speech.

“Even if Khalil ultimately prevails in court, the government’s short-term victory lies in sending a clear message to immigrants at all levels: speaking out on controversial issues could lead to arrest, detention, and potential deportation—regardless of legal standing,” Mr. Vladeck explained.

Mr. Trump has previously leveraged federal powers to suppress protest movements.

In 2020, amid nationwide protests against police brutality and racial injustice, he deployed various federal agencies—including the Bureau of Prisons and Customs and Border Protection—to crack down on demonstrators in Washington, D.C. His administration even authorized the use of military helicopters to fly at low altitudes over protest sites to disperse crowds.

Additionally, his administration explored invoking the Hobbs Act, a 1940s-era law targeting labor racketeering, as a means to prosecute demonstrators.

At the same time, Mr. Trump has displayed leniency toward protests aligned with his own political views.

Upon taking office in January, one of his first acts was granting clemency to nearly 1,600 individuals convicted of both violent and nonviolent offenses related to the January 6, 2021, attack on the U.S. Capitol. Among them were individuals charged with assaulting law enforcement officers and engaging in seditious conspiracy. The rioters stormed the Capitol in Mr. Trump’s name following the 2020 election victory of Joseph R. Biden Jr.