WASHINGTON — The Supreme Court seemed ready to rule on Monday that immigrants allowed to stay in the United States temporarily for humanitarian reasons may not apply for green cards if they had entered the country unlawfully.
The case, which could affect tens of thousands of immigrants, was brought by Jose Sanchez and Sonia Gonzalez, natives of El Salvador who entered the United States unlawfully in the late 1990s. In 2001, after earthquakes devastated El Salvador, the United States made that country’s nationals eligible for the “temporary protected status” program, which shields immigrants from parts of the world undergoing armed conflicts and natural disasters from deportation and allows them to work in the United States.
Mr. Sanchez and Ms. Gonzalez, a married couple, were granted protection under the program. In 2014, they applied for lawful permanent residency, commonly known as a green card. After their application was denied, they sued.
The United States Court of Appeals for the Third Circuit, in Philadelphia, ruled against them, saying they were ineligible under a part of the immigration laws that requires applicants to have been “inspected and admitted” into the United States.
Temporary protected status, Judge Thomas M. Hardiman wrote for the unanimous three-judge panel, “does not constitute an admission.”
“As its name suggests,” he wrote, “this protection is meant to be temporary.”
The law has interlocking provisions, some of which are hard to reconcile, Justice Stephen G. Breyer said. “I have to admit that the immigration statute is pretty complicated,” he said.
Amy M. Saharia, a lawyer for the couple, relied on another provision, this one saying that people granted temporary protected status “shall be considered as being in, and maintaining, lawful status as a nonimmigrant.” She said that meant they had effectively been admitted to the United States.
“Having been inspected and admitted,” she said, “is inherent in having nonimmigrant status.”
The argument met with resistance from the justices.
“I can’t follow the logic of your main submission,” Chief Justice John G. Roberts Jr. told Ms. Saharia.
Justice Clarence Thomas noted that the couple “clearly were not admitted at the borders.”
“So is that a fiction?” he asked. “Is it metaphysical? What is it? I don’t know.”
Justice Brett M. Kavanaugh said, “You have an uphill climb, textually speaking.” He added that the court could let Congress address the matter.
Michael R. Huston, a lawyer for the federal government, said that many people with temporary protected status can apply for green cards — so long as they had entered the country lawfully. “They need to have been admitted as a student or an au pair or a temporary worker or something like that,” he said.
The case, Sanchez v. Mayorkas, No. 20-315, put the Biden administration in a difficult spot. It sought to win only provisionally while leaving room for it to change the government’s approach.
Chief Justice Roberts said there was a tension in the administration’s position and suggested that it had softened the government’s stance after the election.
“I was struck by the extent to which your brief undersold your position,” he told Mr. Huston.
“Throughout it,” the chief justice said, “you said things like the text doesn’t foreclose your position; the court was not required to accept the petitioners’ reading; the statute does not clearly exclude your reading; Congress did not unambiguously mandate the opponent’s position.”
“And, of course,” he said, “you ended by saying that it would not be entirely unreasonable for the court to rule in your favor.”
“I made that last one up,” Chief Justice Roberts admitted, “but that’s what I was expecting to see.”