New York Times

WASHINGTON — Faced with the prospect of definitively resolving the status of Puerto Rico, the Supreme Court on Wednesday explored ways in which to render a narrow decision. But a lawyer for the Obama administration was adamant that the court’s decision should be based on the fundamental ground that the commonwealth is a territory of the United States without independent sovereignty.

The case concerned the Constitution’s double jeopardy clause, which forbids subsequent prosecutions for the same crimes. The Supreme Court has said that the federal government and the states are independent sovereigns, meaning that the same conduct can be prosecuted separately in state and federal courts.

The question in Wednesday’s case, Puerto Rico v. Sánchez Valle, No. 15-108, was whether Puerto Rico was also a separate sovereign and therefore able to pursue a subsequent prosecution for the same crime after a federal conviction. Whether Puerto Rico is a separate sovereign is a deeply contested matter of politics and pride.

The case involves Luis M. Sánchez Valle and Gómez Vázquez, who were prosecuted on gun charges in local and federal courts in Puerto Rico. They pleaded guilty to the federal charges and asserted that they could not be prosecuted for the same crimes in local courts under the Constitution’s double jeopardy clause.

Puerto Rico’s Supreme Court agreed. “Puerto Rico’s authority to prosecute individuals is derived from its delegation by United States Congress and not by virtue of its own sovereignty,” the court’s majority said.

Justice Stephen G. Breyer urged the court to limit its decision to the context of double jeopardy.

“If we simply write an opinion and it says Puerto Rico is sovereign, that has enormous implications,” he said. “On the other hand, if we write an opinion that says it’s just a territory, that has tremendous implications.”

“So either way,” he said, “between those two, the implications in law and in politics and everything else are overwhelming.”

After the case reached the United States Supreme Court, the Obama administration filed a brief saying that Puerto Rico was a territory without independent sovereignty. In a footnote, it acknowledged that this was a change in the federal government’s position.

“In briefs filed two decades ago,” the footnote said, “the Department of Justice argued that Puerto Rico was a separate sovereign for double jeopardy purposes. Those briefs do not reflect the considered view of the executive branch.”

The brief drew an outraged response from Puerto Rico’s governor, Alejandro J. García-Padilla. Saying that the federal government had “abruptly reversed course,” he wrote to the United Nations in protest. The brief, he said, took the position that “there can be no such thing as meaningful self-government by the people of Puerto Rico.”

Justice Breyer asked Nicole A. Saharsky, a lawyer for the federal government, if its position rested on the broad proposition that Congress is free to override Puerto Rico’s Constitution.

Ms. Saharsky said the question was a weighty one and “the answer is yes.” The federal Constitution, she said, has only two relevant categories: states and territories. Puerto Rico is a territory, she said, meaning it is not sovereign.

But Justice Anthony M. Kennedy said there might be varieties of sovereignty, which he called “a slippery word.”

Christopher Landau, a lawyer for Puerto Rico, tried to keep the case narrow.

“Nobody’s asking the court to make a broad political statement,” he said. “All we want to know is may Puerto Rico, may the commonwealth prosecutors, prosecute these particular Puerto Rico commonwealth gun charges?”

Nonetheless, Mr. Landau concluded his argument on an emotional note. “Please do not take the Constitution of Puerto Rico away from the people of Puerto Rico,” he said.