When federal agents arrested Columbia graduate student Mahmoud Khalil this month, he was reportedly told that his student visa was being revoked. The supposed offense: leading protests denouncing Israel’s war in Gaza on the school’s New York City campus last year. When Khalil said he was a permanent resident with a green card, he was told that status was being revoked by the State Department.

Secretary of State Marco Rubio told CBS’s “Face the Nation” on Sunday that the Trump administration will continue to revoke the legal immigration status of folks he terms “Hamas supporters” in order to deport them. Rubio’s bold assertion may succeed in court thanks to a rarely used power the secretary of state possesses that can circumvent other statutes that could have protected Khalil from arrest and deportation.

President Donald Trump’s advisers and administrators have been laser-focused on finding potential edge cases in the law, that is, areas where loopholes and emergency powers can be exploited.

A 1990 update to the Immigration and Nationality Act says the rules that let the State Department deny a noncitizen admission into the U.S. can also be used to make a legal alien eligible for deportation. Immigrants can’t be barred from entry for holding beliefs that would be legal in the United States and, for now at least, there’s no question that believing Israel’s war in Gaza should end is, in fact, still legal for American citizens, as is protesting universities’ support in that war.  But the law makes an exception if “the Secretary of State personally determines that the alien’s admission would compromise a compelling United States foreign policy interest.”

President Donald Trump’s advisers and administrators have been laser-focused on finding potential edge cases in the lawthat is, areas where loopholes and emergency powers can be exploited. In the flurry of executive orders issued from the White House, agencies have consistently been told to comply with their instructions “to the maximum extent of the law.” But that boilerplate language obscures how this administration is pushing the limits and trying to establish a new normal where there are no checks on whatever the president wants to do.

Admittedly, the federal code is filled with laws that leave plenty room for bad-faith interpretation. Congress has developed a habit of writing bills that allow the executive branch to bypass lawmakers in case of emergency or otherwise divest authority on the details of how the law will be executed. The Trump administration seeks to trigger those authorities in ways that Congress may not have intended, and the courts may not agree with, to give the veneer of legality as they proceed with their plans.

In Khalil’s case, leapfrogging the normal immigration channels means the Trump administration doesn’t need to accuse Khalil of a crime. Under this reading, as Trump lawyer Alina Habba told Fox Newseven handing out of pamphlets the administration doesn’t like could be grounds for deportation.

Trump is trying to use every legal provision, regardless of how flimsy, to justify the mass deportations that are central to his immigration policy. On the first day of this term, he declared an “emergency” along the southern border, invoking the powers granted in the National Emergencies Act to mobilize resources and the armed forces. Trump also issued a proclamation declaring that an “invasion” is ongoing, and that he would use the “inherent powers to control the borders” he possesses, regardless of the limitations of the Immigration and Nationality Act.

Those orders became the foundation on which his administration invoked the Alien Enemies Act to rapidly deport Venezuelans it accused of gang activity this weekend. The 1798 statute was part of the infamous Alien and Sedition Actswhich were passed in a time of quasi-war against France and Britain. In the proclamation announcing the policyTrump claimed that the law grants him the authority to expel Tren de Aragua, a gang designated as a terrorist organization under another questionable executive order. A federal judge paused the administration’s use of the law in an order issued Saturday, but an unknown number of immigrants have now been deported to El Salvador, even though many of them reportedly have no proven connection to the gang in question.

Meanwhile, Trump officials continue to hunt for the slightest pretense to invoke other emergency powers. The administration is reportedly looking for a reason to use Title 42a public health provision triggered early in the pandemic, to fully close the southern border again. Trump is waiting on a report from the Pentagon and Department of Homeland Security on whether he should call upon the Insurrection Act’s powers to deploy the military deeper into the United States. Civil liberties groups fear the 1807 law could be used to stifle civil protests, as Trump advocated during his first termwrongly transforming the armed forces and National Guard into a domestic police force.

The administration has also been busy in other areas finding weak points in the law to consolidate power. Office of Management and Budget Director Russel Vought has been especially adept at playing this game. Even before being sworn-in, he had helped draft orders that twisted the rules for hiring special government employees to quickly staff up the Department of Government Efficiency. He has since then been finding ways to skirt federal employment laws to downsize the governmenteffectively shuttering whole agencies and encouraging department heads to illegally fire staffers by deliberately misusing the authorities granted to fire “probationary” workers for their performance.

There’s a term in medicine for when a previously benign bit of biological code gets twisted and begins attacking the rest of the body: a cancer.

And where there is no foothold in the U.S. Code to exploit, the Trump administration has argued even greater authority: Article II of the Constitution. Justice Department lawyers have already claimed a constitutional power to ignore judges’ rulings on foreign affairs in the Alien Enemies Act case and defended his ability to impound whatever money he doesn’t want to spend. In a proclamation on defending the states from “invasion,” Trump claimed that under his Article II role as commander-in-chief of the military, he has a duty under Article IV, Section 4, to repel whatever immigrants he says shouldn’t enter the country.

Trump’s infamous 2019 claim that Article II means “I have to the right to do whatever I want as president” has thereby gone from the simplistic notion of a political neophyte to the core tenet of his second administration. And the GOP-controlled Congress has been quick to quietly bolster existing gray areas of the law to grant him even more leeway. For example, in passing the recent six-month spending bill, the House explicitly stripped away Congress’ power to challenge Trump’s use of the National Economic Emergencies Act in deploying his tariffs.

There’s still a chance the courts override Rubio’s determination on Khalil’s deportability. The government will likely have to establish how it reached its conclusion about the supposed foreign policy threat the Columbia grad student poses. (Rubio was also supposed to notify Congress of his decision, but no such notification has been reported as of Tuesday.) But if Rubio is willing to make that call in this case, how hard would it be for him to keep the ball rolling? What other “foreign policy interests” could be used to hastily deport legal permanent residents? It is a twisting of the intent of the law to bypass due process and establish a norm that could stifle dissent among American citizens as well. Trump has long been keen on the idea of being able to strip protestors of their citizenship; it would be foolish to put it past this administration to try it given the groundwork now being laid.

These attacks on the system from within are ongoing. In Khalil’s case and others, we are seeing the arcane nature of the U.S. federal bureaucracy being used as a weapon against itself. There’s a term in medicine for when a previously benign bit of biological code gets twisted and begins attacking the rest of the body: a cancer.

Congress and the courts need to excise this tumor before it metastasizes. It needs to happen soon though, as the prognosis for the rule of law is otherwise grim.

Hayes Brown

Hayes Brown is a writer and editor for BLN Daily, where he helps frame the news of the day for readers. He was previously at BuzzFeed News and holds a degree in international relations from Michigan State University.