Palestinian activist takes case to US Supreme Court

Columbia University graduate Mahmoud Khalil has asked the US Supreme Court to overturn a ruling that opened the door for President Donald Trump's administration to re-arrest and deport the Palestinian activist.

Khalil's lawyers asked the justices to take up his case after the Philadelphia-based 3rd US Circuit Court of Appeals ruled that federal immigration law barred a lower-court judge from ordering his release from US Immigration and Customs Enforcement custody.

Khalil was among the most prominent foreign students to be arrested in 2025 as the Trump administration pursued a campaign to detain and deport non-citizens who engaged in pro-Palestinian activism on college campuses.

His lawyers say the Supreme Court should make clear immigration law does not prevent non-citizens from pursuing cases arguing they have been detained to punish them for speech that is protected by the US Constitution's First Amendment.

"If the Trump administration can punish someone for their pro-Palestine speech, this or any future administration can punish anyone for any speech," Khalil told reporters on Monday.

If the 3rd Circuit's decision is allowed to stand, Khalil faces the prospect of arrest and deportation, after the Board of Immigration Appeals in April rejected his challenge to an immigration judge's order that he be removed to Algeria or Syria.

A lower court order barring him from being re-detained remains in place for now until the Supreme Court rules. A separate appeal of the immigration judge's order remains pending.

A spokesperson for the US Department of Homeland Security, which oversees ICE, in a statement said the Trump administration acted within its authority in Khalil's case, and it encouraged him to self-deport.

Immigration agents arrested Khalil in March 2025 in the lobby of his university residence in Manhattan despite his being a lawful permanent resident, or green-card holder. His wife and their one-year-old son are both US citizens.

Secretary of State Marco Rubio had invoked an obscure provision of the Immigration and Nationality Act to deem Khalil removable, citing his involvement in "anti-Semitic protests and disruptive activities" at Columbia in 2024 that the government said fostered a hostile environment for Jewish students.

He was released from a Louisiana detention centre in June 2025 after the New Jersey-based US District Judge Michael Farbiarz, ordered the Department of Homeland Security to release him.

In January, a 2-1 panel of the 3rd Circuit overturned Farbiarz's decision, saying that under the Immigration and Nationality Act, Khalil's claims could not be addressed through a district court and instead could be raised in an appeal of a removal order from an immigration judge.

After the full appeals court declined to reconsider the case, Khalil turned to the Supreme Court.