A federal judge in New Hampshire is set to hear arguments on Thursday about the possibility of certifying a class-action lawsuit that encompasses all babies impacted by President Donald Trump’s policy changes on birthright citizenship.

This lawsuit represents a pregnant woman, two parents, and their infants and challenges Trump’s directive from January, which denies citizenship to children born to individuals residing in the U.S. either illegally or temporarily. The plaintiffs, supported by the American Civil Liberties Union and other groups, are aiming to have their lawsuit recognized as a class action and to halt the enforcement of the directive while the case is ongoing.

“In mere weeks, tens of thousands of infants and their parents stand to suffer from the detrimental effects of the order, necessitating an immediate injunction,” the plaintiffs’ lawyers asserted in court documents submitted on Tuesday.

At issue is the Constitution’s 14th Amendment, which states: “All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States.” The Trump administration says the phrase “subject to the jurisdiction thereof” means the U.S. can deny citizenship to babies born to women in the country illegally, ending what has been seen as an intrinsic part of U.S. law for more than a century.

“Prior misimpressions of the citizenship clause have created a perverse incentive for illegal immigration that has negatively impacted this country’s sovereignty, national security, and economic stability,” government lawyers wrote in the New Hampshire case. “The Constitution does not harbor a windfall clause granting American citizenship to … the children of those who have circumvented (or outright defied) federal immigration laws.”

Legal battles continue in multiple states

Several federal judges have issued nationwide injunctions stopping Trump’s order from taking effect, but the U.S. Supreme Court limited those injunctions in a June 27 ruling that gave lower courts 30 days to act. With that time frame in mind, opponents of the change quickly returned to court to try to block it.

New Jersey and the more than dozen states joining its case in Massachusetts federal court have asked the judge to determine if the nationwide injunction in their case could still apply under the high court’s ruling. The judge has scheduled a hearing for July 18.

“Everybody knows there’s a 30-day clock, so our hope is that we get an answer prior to the end of the 30-day clock,” New Jersey Attorney General Matt Platkin told The Associated Press in a recent interview.

In a Washington state case before the 9th U.S. Circuit Court of Appeals, the judges have asked the parties to write briefs explaining the effect of the Supreme Court’s ruling. Washington and the other states in that lawsuit have asked the appeals court to return the case to the lower court judge.

As in New Hampshire, the plaintiff in a Maryland seeks to organize a class-action lawsuit that includes every person who would be affected by the order. The judge set a Wednesday deadline for written legal arguments as she considers the request for another nationwide injunction from CASA, a nonprofit immigrant rights organization.

Ama Frimpong, legal director at CASA, said the group has been stressing to its members and clients that it is not time to panic.

“No one has to move states right this instant,” she said. “There’s different avenues through which we are all fighting, again, to make sure that this executive order never actually sees the light of day.”

New Hampshire plaintiffs include parents, babies

The New Hampshire plaintiffs, referred to only by pseudonyms, include a woman from Honduras who has a pending asylum application and is due to give birth to her fourth child in October. She told the court the family came to the U.S. after being targeted by gangs.

“I do not want my child to live in fear and hiding. I do not want my child to be a target for immigration enforcement,” she wrote. “I fear our family could be at risk of separation.”

Another plaintiff, a man from Brazil, has lived with his wife in Florida for five years. Their first child was born in March, and they are in the process of applying for lawful permanent status based on family ties — his wife’s father is a U.S. citizen.

“My baby has the right to citizenship and a future in the United States,” he wrote.

___ Catalini reported from Trenton, New Jersey.