The Trump administration has undertaken a radical attempt to deport Mahmoud Khalil, a permanent U.S. resident and Palestinian activist. Immigration agents took him into custody on Saturday at Columbia University, where he had helped organize and negotiate on behalf of the group Columbia University Apartheid Divest.

But the administration has offered little concrete justification for why it thinks it has the right to deport Khalil in the first place. The administration has admitted Khalil did not break any laws — and instead, they’ve offered vague allegations and promised more arrests of activists in the near future, potentially using software to sift through social media posts.

The Trump administration’s muddy rhetoric justifying Khalil’s deportation continued Thursday, when a top Homeland Security official hemmed and hawed for five minutes as an NPR reporter tried to get a straight answer out of him.

Asked by NPR’s Michel Martin what “specific conduct” Khalil allegedly engaged in that would merit his removal from the United States, DHS Deputy Secretary Troy Edgar simply wouldn’t say directly.

Describing Khalil as a student who entered the country on a visa — Khalil is a permanent resident with a green card — Edgar said Khalil came in as “a student that is not going to be supporting terrorism” but later had allegedly been “promoting this antisemitism activity at the university.”

The State Department, Edgar said, “revoked his visa for supporting that terrorist-type organization.” (Martin repeatedly corrected Edgar, noting Khalil had a green card.)

“What specifically constituted terrorist activity that he was supporting?” Martin pressed.

“Agitating and supporting Hamas,” Edgar eventually said.

“How did he support Hamas? Exactly what did he do?” Martin asked.

“I think you can see it on TV, right?” Edgar replied. “This is somebody that we’ve invited, and allowed this student to come into the country, and he’s put himself right in the middle of the process — of basically, pro-Palestinian activity.” Secretary of State Marco Rubio can review his “visa process” at any point, Edgar added.

“Is any criticism of the Israeli government a deportable offense?” Martin asked.

Edgar didn’t answer directly, instead saying, “at any point, we can go through and evaluate what his status is.”

“Is any criticism of the United States government a deportable offense?” Martin asked.

Edgar didn’t answer directly. Martin asked the same question. Edgar responded with a hypothetical, in which Khalil had told immigration authorities initially that “‘I’m going to go and protest and join antisemitic activities.’ We would never let him into the country.”

“Is protesting a deportable offense?” Martin pressed.

Again, Edgar wouldn’t answer.

“If he would have declared he’s a terrorist, we never would have let him in,” the DHS official said.

“And what did he engage in that constitutes terrorist activity?” Martin asked.

“I mean, Michel, have you watched it on TV? It’s pretty clear,” Edgar said.

“No it isn’t,” Martin said, asking Edgar to explain.

“I think it’s clear, or we wouldn’t be talking about it. The reality is, if you watch and see what he’s done on the university —”

Martin interrupted: “Are you telling us that you’re not aware?”

“I find it interesting that you’re not aware,” Edgar shot back.

Without any concrete response from the administration, Martin ended the interview.

“The conflation of protest and terrorism stopped me cold,” Will Creeley, legal director of the Foundation for Individual Rights In Education, a free speech group, commented on X, formerly Twitter.

The interview followed a pattern for Donald Trump’s administration, which has refused — or been unable — to give any specific examples of Khalil engaging in violent behavior or otherwise doing anything that might justify the revocation of his permanent residency.

Instead, they’ve alleged that he “led activities aligned to Hamas, a designated terrorist organization” or that he “distributed pro-Hamas propaganda” — all impossibly vague allegations that could serve to suppress the free speech of countless others.

In the end, the Trump administration says Khalil is eligible to be deported because they assert his presence in the United States could “have potentially serious adverse foreign policy consequences for the United States” — obscure legal language that’s only been cited once in recent memory, against a former deputy attorney general of Mexico living in the United States, Georgetown University law professor Stephen Vladeck told The New York Times.

“The government certainly appears to be retaliating for constitutionally protected, even if offensive, speech,” Vladeck told the Times.

While green card holders can be deported for committing immigration violations or crimes — such as violent crime or fraud — everyone in the United States, including permanent residents and visa holders, is covered by the U.S. Constitution and its First Amendment protections. The effort to deport Khalil will be a major legal test of Trump’s efforts to crack down on what he calls “anti-American activity.”

Now, with Khalil’s wife eight months pregnant, the former Columbia grad student is behind bars at an Immigration and Customs Enforcement facility in Louisiana, cut off from communication with his attorneys, they said at a hearing Wednesday.