The Trump administration has made these investigations a bigger priority, he said. He said he expects cases will focus on deliberate fraud but some naturalized Americans may feel uneasy with the change.
"It is clearly true that we have entered a new chapter when a much larger number of people could feel vulnerable that their naturalization could be reopened," Chishti said.
For many years, most U.S. efforts to strip immigrants of their citizenship focused largely on suspected war criminals who lied on their immigration paperwork, most notably former Nazis.
Since 1990, the Department of Justice has filed 305 civil denaturalization cases, according to statistics obtained by an immigration attorney in Kansas who has defended immigrants in these cases.
The attorney, Matthew Hoppock, agrees that deportees who lied to get citizenship should face consequences but worries other immigrants who might have made mistakes on their paperwork could get targeted and might not have the money to fight back in court.
Cissna said there are valid reasons why immigrants might be listed under multiple names, noting many Latin American immigrants have more than one surname. He said the U.S. government is not interested in that kind of minor discrepancy but wants to target people who deliberately changed their identities to dupe officials into granting immigration benefits.
"The people who are going to be targeted by this — they know full well who they are because they were ordered removed under a different identity and they intentionally lied about it when they applied for citizenship later on," Cissna said. "It may be some time before we get to their case, but we'll get to them."