ICE has broad power to detain and arrest noncitizens – but is still bound by constitutional limits

News reports of noncitizens unexpectedly being detained by Immigration and Customs Enforcement, or ICE, have dominated headlines in recent weeks. Those being detained include noncitizens who hold lawful permanent residency status.

One story concerns the March 8, 2025, arrest of Mahmoud Khalil, a lawful permanent resident and recent Columbia University graduate, who was initially detained in New Jersey and transported to Louisiana. He remains there while he challenges his detention and the immigration judge’s April 11 decision that he can be deported

And on March 25, ICE agents arrested Rumeysa Ozturk, a Turkish national and doctoral student at Tufts University, while she was walking on the streets of Somerville, Massachusetts. She is currently detained in Louisiana.

ICE agents have also detained and removed, among other people, hundreds of Venezuelan noncitizens to El Salvador since March, resulting in high-profile legal cases that are making their way through the court system. And the U.S. has revoked the visas of at least 300 foreign students this year.

As a scholar of immigration and citizenship law, I think that it is important to help the public understand the scope and limitations of ICE’s authority.

At the most basic level, ICE has broad, sweeping powers to question, arrest, detain and process the deportation any noncitizen. But ICE is still bound by certain constitutional and other legal restrictions, including noncitizens’ rights to make their case in court to remain in the U.S.

Read the full article here.