As the White House press secretary openly floats the idea of investigating New York City mayoral candidate Zohran Mamdani to possibly strip him of his citizenship, after a bigoted proposal from Rep. Andy Ogles, R-Tenn., the administration appears to be revving up its denaturalization plans.

NPR reported Monday on a Justice Department memo from June 11, which advises prosecutors in the DOJ’s Civil Division to prioritize the denaturalization of various naturalized citizens over alleged infractions ranging from war crimes to “material misrepresentations” in their citizenship applications.

In his first term, Trump expanded former President Barack Obama’s denaturalization policies. An expert told NPR why the new memo’s call to use civil litigation for this effort is particularly disturbing:

The DOJ memo says that the federal government will pursue denaturalization cases via civil litigation — an especially concerning move, said Cassandra Robertson, a law professor at Case Western Reserve University. In civil proceedings, any individual subject to denaturalization is not entitled to an attorney, Robertson said; there is also a lower burden of proof for the government to reach, and it is far easier and faster to reach a conclusion in these cases. Robertson says that stripping Americans of citizenship through civil litigation violates due process and infringes on the rights guaranteed by the 14th Amendment.

On the heels of Friday’s Supreme Court ruling in the birthright citizenship case — which undercut lower courts’ ability to stop the executive branch from pursuing policies of disputed legality — it’s safe to wonder whether and how the administration might wield its powers to target more Americans.

The DOJ memo asserts a broad latitude for interpretation as to what conduct might warrant denaturalization proceedings against a citizen. It lays out a list of transgressions, including torture and human trafficking, but also calls on the DOJ’s Civil Division to target “an individual that either ‘illegally procured’ naturalization or procured naturalization by ‘concealment of a material fact or by willful misrepresentation’” and, rather vaguely, “individuals who pose a potential danger to national security.” The memo also prioritizes the ominously open-ended “any other cases ... that the Division determines to be sufficiently important to pursue.”