A divided federal appeals court on Friday declined to reconsider a ruling in Columbia University graduate Mahmoud Khalil's case that opened the door to US President Donald Trump's administration re-arresting and deporting the pro-Palestinian activist.

The 3rd US Circuit Court of Appeals, on a 6-5 vote, rejected Khalil's request to revisit a ruling a 2-1 panel of the Philadelphia-based court delivered in January that had concluded a lower-court judge had no jurisdiction to order his release from immigration detention last year.

He was among the most prominent of a number of foreign students detained last year by immigration authorities after engaging in pro-Palestinian activism on their college campuses as part of a broad effort by the Trump administration.

Six judges appointed by Republican presidents were in the majority, while five Democratic appointees voted to rehear the case, including US Circuit Judge Cheryl Ann Krause, who said the court's decision handcuffed the judiciary's ability to protect the civil liberties of non-citizens like Khalil.

Activist and former Columbia University student Mahmoud Khalil attends a 100 Days Rally for Mayor Zohran Mamdani at the Knockdown Center in New York, NY, USA on April 12, 2026.
Activist and former Columbia University student Mahmoud Khalil attends a 100 Days Rally for Mayor Zohran Mamdani at the Knockdown Center in New York, NY, USA on April 12, 2026. (credit: Jason Alpert-Wisnia / Hans Lucas / AFP via Getty Images)

"We cannot fulfill that role if we write ourselves out of relevance and leave the Executive Branch to check itself," wrote Krause, who was appointed by Democratic President Barack Obama.

Lawyer: Khalil in 'brutal detention conditions'

Baher Azmy, a lawyer for Khalil at the Center for Constitutional Rights, in a statement vowed to ask the US Supreme Court to hear Khalil's case and overturn the 3rd Circuit's "dangerous" decision.

“That ruling greenlights holding someone in prolonged, brutal detention conditions without access to meaningful judicial review in order to punish them and deter others from dissenting from US foreign policy," he said.