Explainer: US arrest of pro-Palestinian activist Mahmoud Khalil

Mahmoud Khalil, an Algerian citizen of Palestinian descent, was arrested on Saturday by US Immigration and Customs Enforcement (ICE) at his Columbia University-owned apartment in upper Manhattan in New York City.

A recent graduate of the university’s School of International and Public Affairs, Khalil has been a leading figure in pro-Palestinian activism at Columbia, including the Gaza Solidarity Encampment.

In 2024, pro-Palestinian student encampments emerged across the US as part of broader protests against Israeli attacks in Palestine. These encampments were a key component of the student-led movement demanding that universities divest from companies supporting Israel.

Khalil, a legal permanent resident of the US, has been a prominent figure in these movements.

His arrest has sparked widespread outrage, raising questions about free speech, immigration policies and the targeting of activists.

Khalil’s activism made him a visible target amid growing tensions over campus protests and the Trump administration’s crackdown on what it deems “anti-American” activities.

Why was Khalil detained?

Khalil’s arrest followed an executive order by US President Donald Trump targeting “pro-terrorist, anti-Semitic, anti-American activity” on college campuses.

“We know there are more students at Columbia and other Universities across the Country who have engaged in pro-terrorist, anti-Semitic, anti-American activity, and the Trump Administration will not tolerate it,” he said.

Authorities initially tried to revoke Khalil’s visa but later learned that he is a permanent resident and moved to revoke his green card, with the Department of Homeland Security accusing him of activities “aligned with” the Palestinian group Hamas.

Secretary of State Marco Rubio defended the move, stating: “Coming to the United States on a visa is a privilege, not a right,” and accused Khalil of supporting Hamas.

Trump called Khalil’s detention “the first arrest of many”, signalling a broader crackdown on pro-Palestinian activism.

Additionally, Trump has targeted Columbia University, questioning whether it has done enough to prevent what he describes as antisemitic incidents. Earlier this month, his administration cancelled $400 million in federal grants and contracts to the institution.

Judicial process

Khalil was first detained in New Jersey before being moved to the LaSalle Detention Centre in Louisiana, a facility known for housing immigration detainees.

A federal judge temporarily blocked his deportation on Monday. Judge Jesse Furman ordered that Khalil not be removed from the US until further court proceedings, emphasising the need to preserve jurisdiction over the case.

During a hearing on Wednesday, Furman also granted Khalil access to his legal team after attorneys raised concerns about limited communication.

A separate hearing is scheduled for March 27 in immigration court to determine the validity of Khalil’s green card status.

Justice Department lawyers argued for the case to be moved out of New York, proposing New Jersey or Louisiana as alternative venues.

Reactions to detention

Khalil’s arrest has drawn widespread condemnation from human rights organisations, lawmakers and activists.

The American Civil Liberties Union (ACLU) called the detention “unprecedented, illegal, and un-American”, accusing the government of targeting individuals for their political views.

Agnes Callamard, Amnesty International’s Secretary General, described the arrest as “deeply shocking” and a violation of fundamental US values, including freedom of expression.

The United Nations also emphasised the importance of upholding the right to peaceful assembly and free speech.

Lawmakers, including Senator Bernie Sanders and Representatives Rashida Tlaib, Ilhan Omar and Ayanna Pressley, have condemned the detention.

Sanders called it an illegal attempt to suppress political dissent, while 14 members of Congress signed a letter demanding Khalil’s release, labelling his arrest a “direct assault on freedom of speech”.

Protests have erupted across the US, with more than 1,000 demonstrators gathering in New York City on Monday to denounce the arrest as political persecution.

Protesters criticised the administration’s efforts to silence dissent, with one saying “the US is enacting many laws and executive orders to prevent us from expressing our opinion, from defending Palestinians, from defending human rights.”

Trump’s border czar Tom Homan also faced protests during a visit to New York state’s capitol, Albany. Demonstrators, including assemblyman Zohran Mamdani, criticised Homan’s role in implementing harsh immigration policies and the detention of Khalil.

“Do you believe in the First Amendment?” Mamdani shouted at Homan.

On Thursday, hundreds of activists staged a sit-in at Trump Tower in New York City, resulting in nearly 100 arrests.

Broader implications

Khalil’s case has become a flashpoint in the ongoing debate over free speech, immigration and national security.

Critics argue that the Trump administration is using immigration enforcement to target political opponents and suppress activism, particularly on college campuses. The case also highlights the administration’s broader efforts to restrict pro-Palestinian advocacy, which has surged in response to Israel’s devastating campaign in Gaza, which has killed more than 48,500 people, mostly women and children, and left the enclave in ruins with accusations of genocide.

The outcome of his case could set a precedent for how the US government handles similar situations in the future, with significant implications for free speech and immigration policy.

In the meantime, Khalil remains in detention, separated from his wife, an American citizen, who is eight months pregnant, and facing an uncertain future.