The defendant was elsewhere, stirring and twittering in his new city, his name rarely spoken — just the title sufficed — but always top of mind inside an overstuffed Manhattan courtroom.

“The president” is a businessman, the plaintiffs’ lawyer reminded the judge. “The president” refuses to leave the marketplace. This is hardly a fair fight, the logic goes, for those who are not “the president.”

“I want to address the government’s view,” said the lawyer, Deepak Gupta, “that the president is above the law.”

Such was the civic exercise on Wednesday — part liberal catharsis theater, part constitutional drama of the highest order — aimed at answering a simple question: Is a sitting president, disinclined to relinquish his gilded empire, violating the Constitution by continuing to own and profit from his businesses?