Acting Attorney General Todd Blanche said Wednesday that federal prosecutors and law enforcement officers will prioritize investigating and prosecuting so-called “birth tourism” schemes, a day after the U.S. Supreme Court ruled 6-3 that President Donald Trump’s executive order restricting birthright citizenship was unconstitutional.

“There’s other things that [the Department if Homeland Security] can do, and the federal government can do in the visa process, and the application process, to try to minimize or limit the opportunity of folks coming here not to visit, and not to do what they’re saying they’re doing on the tourist visa, but just to have a baby that can then be a U.S. citizen,” Blanche told reporters.

“What we have to do as Department of Justice is make sure our agents, our Homeland Security Investigations agents that we work with, and the FBI are focused on stopping that,” Blanche said.

The Justice Department released a memo urging U.S. attorneys to work with the Department of Homeland Security to “prioritize the investigation and prosecution of birth tourism schemes.” Assistant Attorney General Colin McDonald, head of the national fraud division, directed DOJ staff in an office-wide memo to bring fraud charges in alleged cases of birth tourism.

“The Department of Justice will zealously protect the sanctity of United States citizenship by investigating and prosecuting those who fraudulently exploit our immigration system,” McDonald wrote.

Blanche said federal prosecutors will focus on combating businesses and organizations that facilitate birth tourism, even after the Supreme Court left birthright citizenship intact. During oral arguments in the case, the government’s lawyer, D. John Sauer, conceded that “no one knows for sure” how significant a problem birth tourism actually is.

The Center for Immigration Studies, an organization that advocates for reduced immigration, estimated there are between 20,000 and 26,000 births by women on tourist visas annually. This represents less than 1% of all babies born in the U.S. each year.

Chief Justice John Roberts, writing for the majority, said the administration provided “scant evidence for this dramatically revisionist view” of the 14th Amendment’s Citizenship Clause.

Trump is now pushing for lawmakers to create new legislation that would establish exceptions to birthright citizenship for children born to parents who do not have permanent legal status in the U.S. However, any legislation would need to overcome the 60-vote filibuster in the Senate, which has proven difficult for divisive bills during Trump’s second term.

House Speaker Mike Johnson echoed the administration’s concerns at a press conference on Tuesday. “I do think that this has been grossly abused in recent years,” Johnson said. “You just come on to the soil and have your child, and then they’re able to avail themselves of the welfare state and everything else.”

Vice President JD Vance, asked about Justice Amy Coney Barrett’s role in upholding the constitutional right, said he believed she “made a mistake in the ruling.” Vance said he does not believe the framers of the 14th Amendment intended to grant citizenship to children born to someone who “is pregnant and comes to the United States on a vacation.”