WASHINGTON — The Supreme Court seemed prepared on Tuesday to reject a constitutional challenge to the federal response to the worst debt crisis in Puerto Rican history, one that threatened basic services like schools and hospitals, some $50 billion in public pension obligations and more than $70 billion in debts to bondholders.

The crisis got worse after Hurricane Maria destroyed much of the island’s infrastructure in 2017, with the commonwealth estimating that recovery costs will exceed $139 billion.

The Supreme Court argument, which lasted 80 minutes instead of the usual hour, concerned a question of constitutional law: whether members of a government board created by Congress in 2016 to clean up the financial mess had been properly appointed. The court’s answer to that question could undo years of work on restructuring the commonwealth’s debts and help resolve deep questions about its place in the federal system.

The 2016 law at issue in the case — the Puerto Rico Oversight, Management and Economic Stability Act, or PROMESA — created an independent entity to restructure the commonwealth’s debt, the Financial Oversight and Management Board. Since then, the board has tried to resolve about 165,000 claims from creditors, not always to their satisfaction.