Credit Zach Gibson/The New York Times
WASHINGTON — “I really felt like the roof had caved in on me,” Solicitor General Donald B. Verrilli Jr. said the other day, recalling the low point of his five years as the Obama administration’s top appellate lawyer.
Mr. Verrilli, 58, is preparing to step down from the job this month after a tenure that included 37 Supreme Court arguments and a string of major victories on behalf of a Democratic president facing a court dominated by conservative justices. But the scathing reviews of his most important Supreme Court argument, in the 2012 case challenging the constitutionality of President Obama’s health care law, still sting.
Minutes after the presentation was over, Jeffrey Toobin, the CNN legal analyst, said it had been “a train wreck for the Obama administration,” adding that “this law looks like it’s going to be struck down.”
Mr. Verrilli said reviews like that were “quite rough.”
“I won’t kid you,” he said. “It was hard, really hard. Not only because I like to think of myself as a good lawyer, but also this was an incredibly consequential case. It mattered to the president. It mattered to the administration. It mattered to the country.”
The Supreme Court upheld the law, and on grounds that Mr. Verrilli had been instrumental in pressing. Still, he said, the argument began poorly. For starters, he had participated in so many practice sessions that his voice was shot.
“It just seized up on me,” he said, the memory fresh. “And then I took a sip of water and it went down the wrong way and I couldn’t get any words out. It affected my concentration. I definitely lost my concentration at the beginning of the argument.”
“I got off to a really bad start,” he added. “But I thought that over the course of the hour, that I’d basically clawed my way back into the conversation. And then in the last third of the argument, I felt like I was making the points I wanted to make in the way I wanted to make them.”
The points must have landed, as Chief Justice John G. Roberts Jr. accepted Mr. Verrilli’s position that a central requirement of the law was authorized by the congressional power to levy taxes, handing him a stunning 5-to-4 victory.
Mr. Verrilli said he and his colleagues had made a conscious decision “to push the tax argument to the extent we did.”
“That had always been part of the case, but once it got to the Supreme Court, we put a lot of work into making that a stronger argument,” he said. “So I thought the lawyering may have made a difference there.”
Mr. Toobin, for his part, said last week that he had been half-right. “I don’t think I was wrong about the quality of the argument,” he said. “I was wrong about its importance to the resolution of the case.”
Mr. Toobin added: “I think what I am guilty of is ascribing too much importance to oral argument, period. “The justices all say the briefs matter a great deal more than oral arguments. That’s a lesson I keep learning.”
Mr. Verrilli, sitting in his favorite armchair in his hushed office at the Justice Department, said there were no hard feelings.
“Jeff Toobin, I give the guy a lot of credit,” Mr. Verrilli said. “He came in and he apologized.”
Mr. Verrilli said he learned an important lesson from the criticism he had endured. “It’s not a good or healthy thing to have your sense of self-worth determined by what other people are saying,” he said.
“I wish I’d learned that before I was in my mid-50s but, you know, it helped a lot to learn it.”
Last year, Mr. Verrilli prevailed in a second health care case, a challenge to nationwide tax subsidies. And he helped persuade the court to recognize a constitutional right to same-sex marriage.
Mr. Toobin said Mr. Verrilli was at his best in the marriage case. “That was the perfect combination of legal expertise and moral righteousness,” he said. “I don’t know that I ever heard a better argument in the court.”
The loss he most regrets, Mr. Verrilli said, was in 2013, in Shelby County v. Holder, which effectively struck down the heart of the Voting Rights Act of 1965.
“There are some powerful real-world consequences that followed very quickly from that decision,” he said. “It was an iconic statute and an important part of American history. That was a tough loss.”
Mr. Verrilli said he has made no plans beyond taking a long break that will include a trip to Italy. He said he would leave a gift for his deputy, Ian H. Gershengorn, who will now lead the office.
“I’ve become a devotee of throat lozenges,” Mr. Verrilli said. “I’ll always have one in my mouth right before I start an argument. I’ve got a bag of throat lozenges I’m going to leave for him.”
In April, before the last argument of the term, Mr. Verrilli rose to make a final request. He made a motion to admit his wife, Gail W. Laster, to the bar of the Supreme Court.
Mr. Verrilli recited the usual words, saying that he was satisfied that his wife “possesses the necessary qualifications.”
In response, Chief Justice Roberts departed from the script. “You better be,” he said warmly and to laughter.
Mr. Verrilli said the moment would stay with him. “The chief’s joke was really terrific,” he said. “That was really sweet of him, actually.”
Mr. Verrilli will be gone by the last week of the Supreme Court term, when the biggest decisions usually land. In the past, he has been in his usual seat in the courtroom when justices announce their opinions.
This year, he said, the news will reach him soon enough.
“I’ll find out pretty fast, and hopefully I’ll have a glass of Chianti in my hand,” Mr. Verrilli said. “I’m good with it. I’ve had enough moments of high drama sitting in that seat.”