Midnight ruling exposes rifts at a Supreme Court remade by Trump

That said, the court’s dynamics can be complicated, and not all decisions break along predictable lines. For instance, while Chief Justice Roberts has lost his place at the court’s ideological center, his replacement, Justice Brett M. Kavanaugh, Mr. Trump’s second appointee, values consensus and may turn out to be an occasional ally.

On Wednesday, Justice Kavanaugh issued a conciliatory concurring opinion emphasizing that he agreed with much of what Chief Justice Roberts had written in dissent.

“I part ways with the chief justice,” he wrote, “on a narrow procedural point.” That point — whether the court should act immediately, notwithstanding Mr. Cuomo’s decision to lift the challenged restrictions for the time being — was, however, enough to decide the case.

The majority opinion was unsigned, but Ross Guberman, an authority on legal writing and the author of “Point Taken: How to Write Like the World’s Best Judges,” said he suspected that its principal author was the newest justice.