WASHINGTON — The Supreme Court ruled on Thursday that Congress may exclude residents of Puerto Rico from a Social Security benefits program, that a California family may pursue a lawsuit seeking to recover a painting stolen by the Nazis and that a city ordinance regulating off-premises signs did not have to satisfy the most demanding form of First Amendment scrutiny.

Puerto Rico

The case from Puerto Rico concerned a Social Security program that provides monthly cash payments to older, blind and disabled people who cannot support themselves. The benefits, called Supplemental Security Income, are available to U.S. citizens in the 50 states, the District of Columbia and the Northern Mariana Islands, but not in Puerto Rico, the U.S. Virgin Islands and Guam.

The case, United States v. Vaello-Madero, No. 20-303, concerned Jose Luis Vaello-Madero, a disabled man who received the benefits when he lived in New York and continued to get them after he moved to Puerto Rico in 2013. When the Social Security Administration became aware of the move, it sought repayment of the benefits Mr. Vaello-Madero had received since then, eventually suing him for about $28,000.

Mr. Vaello-Madero said the law violated his right to equal protection, winning in the lower courts.

Justice Brett M. Kavanaugh, writing for eight members of the court, said the unequal treatment was justified by the fact that residents of Puerto Rico generally do not pay federal income taxes. “In devising tax and benefits programs,” he wrote, “it is reasonable for Congress to take account of the general balance of benefits to and burdens on the residents of Puerto Rico.”

Justice Kavanaugh noted that Congress was free to strike a different balance. Last year, President Biden said that excluding Puerto Rico from the program was “inconsistent with my administration’s policies and values” and called on Congress to address the matter.

Justice Sonia Sotomayor, whose parents were from Puerto Rico, dissented. “There is no rational basis,” she wrote, “for Congress to treat needy citizens living anywhere in the United States so differently from others.”

Justices Clarence Thomas and Neil M. Gorsuch each issued lengthy concurring opinions. Justice Thomas questioned whether the Fifth Amendment’s due process clause banned the federal government from violating equal protection principles.

Justice Gorsuch wrote that the court should overrule a series of early-20th-century decisions known as the Insular Cases, which ruled that territories acquired by the United States were not automatically entitled to all of the Constitution’s protections.

“The Insular Cases have no foundation in the Constitution and rest instead on racial stereotypes,” Justice Gorsuch wrote. “They deserve no place in our law.”

Stolen Art

The court unanimously ruled that an appeals court had wrongly applied Spanish law in a dispute between the heirs of Lilly Cassirer, who fled Nazi Germany in 1939, and a Spanish museum over the ownership of painting of a Paris streetscape, “Rue Saint-Honoré Après-midi, Effet de Pluie” (“Rue Saint-Honoré in the Afternoon, Effect of Rain”) by Camille Pissarro.

“Although the legal issue before us is prosaic, the case’s subject matter and background are anything but,” Justice Elena Kagan wrote for the court.

Ms. Cassirer surrendered the painting to the Nazis to obtain an exit visa, and she and her family were not able to locate it after the war. After she was declared its rightful owner, Germany in 1958 paid her compensation of about $250,000 in today’s dollars.

The painting eventually turned up in a Spanish museum, a government institution. It is now thought to be worth tens of millions of dollars, Justice Kagan wrote.

Ms. Cassirer’s heirs, who live in Southern California, sued to recover it, prompting lower courts to consider a tangle of questions about whether Spanish or California law governed the case. Under federal law, they concluded, the right answer was Spanish law. And under Spanish law, the family lost.

The correct answer to the initial question, Justice Kagan wrote, was that California rather than federal law should determine which jurisdiction’s laws applied, reopening the case, Cassirer v. Thyssen-Bornemisza Collection Foundation, No. 20-1566, and sending it back to the lower courts for further proceedings.

The Supreme Court’s decision, Justice Kagan wrote, was an interim step and did not resolve the larger question of “whether the Cassirer family can get the painting back.”

Sign Ordinance

The court continued a debate on when the First Amendment requires that laws drawing distinctions based on the content of the speech they regulate must satisfy the most demanding form of judicial review, strict scrutiny.

In 2015, in Reed v. Gilbert, the court struck down an ordinance in Gilbert, Ariz., that had differing restrictions on political, ideological and directional signs.

“Content-based laws — those that target speech based on its communicative content — are presumptively unconstitutional and may be justified only if the government proves that they are narrowly tailored to serve compelling state interests,” Justice Thomas wrote for the majority at the time.

Thursday’s decision concerned an ordinance in Austin that imposed different restrictions on “off-premises signs” — those that advertised goods and services not located where the signs were — than on “on-premises signs.”

Outdoor advertising companies challenged the ordinance, saying it drew distinctions based on the content of the messages the two kinds of signs conveyed.

Justice Sotomayor, writing for the majority, said the Austin ordinance was different from the one at issue in the Reed decision and did not have to satisfy the demanding constitutional test required by it.

“The city’s provisions at issue here do not single out any topic or subject matter for differential treatment,” she wrote. Chief Justice John G. Roberts Jr. and Justices Stephen G. Breyer, Kagan and Kavanaugh joined the majority opinion. Justice Samuel A. Alito Jr., in a partial concurrence, agreed with the majority’s bottom line though not its reasoning.

In dissent, Justice Thomas, the author of the majority opinion in Reed, said the court had misapplied and undermined it.

“Under Reed, Austin’s off-premises restriction is content based,” he wrote. “It discriminates against certain signs based on the message they convey — e.g., whether they promote an on- or off-site event, activity, or service.”

The majority, he wrote, “misinterprets Reed’s clear rule for content-based restrictions and replaces it with an incoherent and malleable standard.”

Justices Gorsuch and Amy Coney Barrett joined Justice Thomas’s dissent in the case, City of Austin v. Reagan National Advertising of Austin, No. 20-1029.