What evidence does the US government need to deport green card holders? 

A Columbia University activist with a green card, a Georgetown University academic with a student visa, a Brown University kidney transplant specialist with a work visa: They are among the people who, despite having legal permission to be in the US, have recently been detained by immigration authorities or denied entry to the US at airports.

President Donald Trump has said he supports legal immigration, and administration officials have given assurances that Trump’s campaign promise of mass deportations would focus on people who have committed violent crimes. But some of the highest-profile examples of attempted deportations are people who have legal permission to be in the US.

Immigration experts said people with visas and green cards have been deported under other administrations, but some of the Trump administration’s actions have been unprecedented.

“The Trump administration has jettisoned typical guidelines and procedures and is looking for arcane passages of immigration law to ensure that it can remove anyone it desires, ideally with limited or no due process,” Matthew Boaz, a University of Kentucky immigration law professor, said.

Columbia University graduate and pro-Palestinian activist Mahmoud Khalil was detained by immigration authorities, who said he could be deported and cited a Cold War-era law. Under that law, the secretary of state can make a noncitizen subject to deportation if their presence or activities could threaten US foreign policy interests. The government has not yet provided evidence for how Khalil has threatened US foreign policy.

Immigration authorities have cited the same Cold War-era law while seeking to deport another Columbia University student involved in the pro-Palestine movement. A federal judge temporarily blocked the student’s detention and deportation.

What evidence do government officials need in these cases, and what are people’s rights?

Immigration experts said the government must show proof to deport a green card or visa holder, but the process can be lengthy. For example, Khalil was arrested on March 8 and has been held in an ICE detention facility in Louisiana as his case proceeds. His lawyers say the detention is unlawful and are trying to transfer the case to New Jersey.

For visa holders at US borders or airports, customs officials can choose to deny people entry without evidence.

What are a few reasons a legal permanent resident could be deported?

People with lawful permanent residence, or a green card, can be deported from the US. But they first have the right to plead their case in court. Only an immigration judge has the power to revoke a green card.

There are several reasons green card holders may be eligible for deportation, including criminal convictions such as rape, murder or drug trafficking.

The government can also deport permanent residents if they commit immigration fraud.

After Khalil had been held in ICE custody for about two weeks, immigration authorities updated his charging documents, accusing him of fraud in his 2024 green card application. The government says Khalil failed to disclose his time working with UNRWA, the United Nations agency for Palestine refugees, and other international groups.

Before the government amended Khalil’s charging document, advocacy groups accused the Trump administration of violating Khalil’s right to free speech. After his arrest, Khalil’s lawyers filed a petition alleging that ICE had arrested and detained Khalil “on the basis of his speech” in a violation of the First Amendment, the American Civil Liberties Union wrote.

Drug-related convictions can also be cause for deportation. Fabian Schmidt, a German engineer and green card holder, was detained after flying back to the US on March 7. Schmidt had a decade-old misdemeanour drug and DUI charge, NPR reported.

Another green card holder, Ma Yang, who has lived in the US since she was eight months old, was deported to Laos in the first week of March after pleading guilty to and serving a sentence for being part of a marijuana trafficking operation, the Milwaukee Journal Sentinel reported.

What evidence does the government have to provide to deport a lawful permanent resident?

The US government must first serve a green card holder with a notice to appear, which is a charging document for immigration cases. In it, the government lists the reasons it believes the person is deportable, Jaclyn Kelley-Widmer, Cornell University immigration law professor, said.

Once someone receives a charging document, an immigration court case is initiated. In court, the US government has the burden of proof and must show through “clear and convincing evidence” – more likely to be true than untrue – that the person can be deported.

The evidence that government lawyers must provide depends on the case. For example, lawyers can use proof of a criminal conviction to show that someone has been convicted of an aggravated felony. Or lawyers could show tax filings to prove someone filed taxes as a nonresident and therefore has abandoned lawful permanent status.

What is the deportation process for people with tourist, student or work visas?

Like legal permanent residents, people with tourist, student or work visas who are already in the US are also given notices to appear if the government believes they are deportable.

Visa holders can be deported for reasons including crime and fraud, if they overstay their visa or if they work without authorisation. Visa holders are afforded the same due process as legal permanent residents, and the government has the burden of proof.

Immigration authorities detained Badar Khan Suri, a graduate student teaching at Georgetown University on a student visa. Suri’s visa has been revoked using the same authority cited in Khalil’s case – that his presence or activities could threaten US foreign policy interests – Politico reported. He is awaiting immigration proceedings.

Visa holders can also be denied entry at an airport or US border, because a visa itself does not grant US entry. Customs and Border Protection officers have the authority to admit people or deny entry. They might deny entry if visa holders have a past criminal conviction, are at risk of overstaying their visas or might be coming to the US to work without authorisation.

For example, in late January, a German tourist who is a tattoo artist was denied after border officials assumed she would illegally work in the US because she was carrying tattoo equipment, The Guardian reported.

Is the Trump administration following the process?

Immigration law experts had differing opinions about whether the Trump administration has followed the legal processes to deport legal permanent residents or visa holders in the US.

“My understanding is, as of right now, they’re following the process,” Boaz, the immigration law professor, said, citing the fact that people have received charging documents and are awaiting court cases. “What’s different is the manner in which it’s being done.”

Boaz said typically people know what type of conduct “would make them a target for removal”, such as not having legal status or having a criminal conviction. That’s not the case under Trump’s administration, as people without criminal convictions and with legal status have been targeted.

Other experts said the administration has deviated from the law.

“Even if the law protects someone from deportation, there is no guarantee today that ICE will abide by the law,” Rebecca Sharpless, University of Miami’s immigration clinic director, said. “People should make choices about things like travel with this reality in mind.”

Immigration agents who arrested Khalil outside his home initially said his student visa had been revoked, although he did not have a student visa, according to the petition filed by Khalil’s lawyers. After Khalil’s wife showed agents that Khalil has a green card, the agents said that was also being revoked.

However, immigration agents can’t revoke legal permanent status; only immigration judges can, after a court proceeding.

“It later came to light that the Department of Homeland Security was charging Mr Khalil” under the Cold War-era provision, the petition said.

The Trump administration also turned away a Brown University doctor at an airport despite a court order preventing it.

Rasha Alawieh, a kidney transplant specialist with a US work visa, was denied entry at an airport after border officials said they found photos of Hezbollah members on her phone, CBS News reported.

Immigration officers said they had not received a judge’s order until after Alawieh had been deported, CNN reported.

The French government said one of its citizens, a scientist, had been denied entry to the US because his phone had messages where he “expressed his ‘personal opinion’ on the Trump administration’s science policies”, Philippe Baptiste, France’s minister for higher education and research, told The New York Times.

“There’s only specific grounds by which somebody can be refused admission to the United States, and disagreeing with Trump, typically, isn’t one of them,” David Leopold, an immigration lawyer and former president of the American Immigration Lawyers Association, said.

What rights do immigrants have when interacting with immigration officials?

People already in the US are protected by the US Constitution. An immigration agent cannot enter people’s homes unless they have a warrant signed by a judge, immigration law experts said. Often, immigration officials have administrative warrants signed by an Immigration and Customs Enforcement officer; those do not carry the same legal weight as a judicial warrant.

To obtain a judicial warrant, immigration officials must “present evidence of a crime to a judge”, Kelley-Widmer said.

At airports, people’s rights vary.

Every traveller is subject to customs officers’ questions about their identity and immigration status. US citizens and green card holders cannot be denied entry to the US, the American Civil Liberties Union wrote. But green card holders can be detained if officers suspect they are deportable. Visa holders can be denied entry if they refuse to answer questions.