At 54, Don Verrilli Jr. stands tall and calm in the Supreme Court chamber, his salt and pepper mustache the only thing about him that bristles. His deep, baritone voice suggests to the justices that he is the essence of reasonableness. There are no histrionics. Indeed, if he gets backed into a corner, his voice just gets deeper. Only the occasional, needless throat-clearing betrays any nerves at all.

He has argued 17 cases before the court, five of them since taking over as solicitor general at the beginning of this term, and next week he will lead the government's defense of the Obama health care overhaul.

Verrilli served in private practice for 25 years, becoming co-chairman of the appellate and Supreme Court practice at the law firm of Jenner & Block. There he was a genuinely beloved figure, the kind of professional younger lawyers seek to emulate. He represented large commercial interests, specializing in communications and First Amendment law.

In one famous case, representing the music recording industry and motion picture companies, he persuaded the court that the developer of an online file-sharing software program was encouraging consumers to steal. It was a landmark and unanimous legal victory that established the principle of paying for even indirect online use of copyrighted music and video.

At the same time, though, Verrilli deliberately allocated 10 percent of his time to pro bono work and became known in particular for handling death penalty appeals. He got interested in the work after clerking for Supreme Court Justice William J. Brennan Jr., a job that had him often working frantically late into the night on last-minute applications for stays of execution.

"The inadequacy of representation really jumped out at me," Verrilli says. "That troubled me, and so once I finished clerking, I said to myself that I was going to devote some portion of my time and energy as a lawyer to trying to do something about that."

He did, arguing five death penalty cases at the Supreme Court and winning two. Perhaps the most celebrated of these was a case in which a death row inmate's lawyer failed to introduce evidence of a horrific and brutal childhood, including physical and sexual abuse. By a vote of 7-2, the court agreed that the failure to introduce that information as mitigating evidence amounted to ineffective assistance of counsel, and the court set aside the death penalty.

"Many of my most fulfilling experiences came out of those kinds of cases," says Verrilli, who ticks off the wide variety of cases that rewarded him professionally but not financially. "I represented Teach for America and I negotiated a settlement of a big public housing discrimination case, and I even represented a Peace Corps volunteer who didn't get her medical benefits."

Success in private practice was not enough for him though, and by the time Barack Obama was elected in 2008, "I would have taken any job, including sweeping the floors, to work in the Department of Justice," Verrilli recalls. "The reason I felt that way was I settled in Washington in the 1980s because I wanted to do public service. And I woke up 25 years later not having done that, and so I thought the time had come."

He took a job that many of his colleagues thought was not important enough for someone of his age and professional stature. He became the associate deputy attorney general, the deputy to the deputy. But he quickly won the admiration of career lawyers and political appointees alike for his balanced approach to the most difficult and complex questions.

Indeed, his unflappability and keen intellect were so appreciated by the White House that the president stole Verrilli for his own staff, making him deputy White House counsel. Those who knew his work sang his praises, while he remained largely unknown to most of official Washington. When it came to nominating a new solicitor general to replace now-Supreme Court Justice Elena Kagan, there was never much doubt in the West Wing as to who would get the job. For "no drama Obama," the quiet and intellectual Verrilli was perfect.

For Verrilli, the new job is quite a change in pace. He was so used to the wild ride of the White House, with its constant demands, that when he became solicitor general and his beeper stopped going off all the time, he thought his BlackBerry was broken.

He soon settled down, however, to a different kind of wild ride, as the guy responsible for coordinating all the government's appeals, arguing the most important ones in the Supreme Court and, from time to time, telling the president or his subordinates that no, they can't do something.

"I know how to say no and I have said no," he says firmly. "If I have to say no in the future, I will."

In the last analysis, though, Verrilli's job is to defend federal laws and actions. He says he has no difficulty arguing positions that are exactly the opposite of the positions he likely would have argued as a private lawyer. In private practice, his clients were typically large communications companies and in representing them, he usually opposed any government regulation of speech.

As the government's lawyer, he is often defending those rules limiting speech. Most recently, he defended a federal law making it a crime to lie about having received a military medal. During the argument, many of the justices expressed some doubts about the government's interest in criminalizing a lie that is nothing more than personal puffery. Verrilli responded with force.

"The honors system is about identifying the attributes, the essence, of what we want in our servicemen and women — courage, sacrifice, love of country, willingness to put your life on the line for your comrades," Verrilli said to the justices. "And for the government to say this is a really big deal and then to stand idly by when one charlatan after another makes a false claim to have won the medal does debase the value of the medal in the eyes of the soldiers."

Supreme Court advocate Tom Goldstein, founder of the leading Supreme Court blog, calls Verrilli "the Democrats' John Roberts," respected by the court as a gentleman and a scholar in the same way that now-Chief Justice Roberts was when he was a private lawyer.

Goldstein acknowledges that Verrilli may not be quite as smooth as Roberts, but adds that "ironically, in the Supreme Court, the justices don't admire smoothness and high rhetoric."

What the justices are looking for, Goldstein says, is "real substance," and "they really trust him. They knew him for a long time in the way that they knew John Roberts as a private advocate. And you can just tell in the tenor of their questions that they believe this guy."

The dirty little secret, though, is that Verrilli's measured public veneer is just that — a veneer. His family and close friends all say he is a passionate Italian, as his name might suggest.

So, does he work at that dispassionate veneer? His answer is an emphatic "yes!"

"I think that I've learned over the years that in order to be effective both professionally and personally, it's important to be passionate or angry — whatever the emotion is — at the right time, in the right way, for the right reasons. And that being that way indiscriminately is usually counterproductive," says Verrilli.

It's a personal policy that has served him well throughout his life. In 1988 he married Gail Laster, a legal force in her own right. The marriage was unusual for only one reason back then: He is white and she is black. Both sets of parents were supportive, but a bit worried. His parents were concerned that an interracial marriage might limit his professional opportunities.

"It was a reasonable fear, I guess, but they weren't right about it," Verrilli says, adding that his parents were also "worried about the ability of our children to make a way in the world as children of an interracial couple, and, so far at least, that doesn't seem to have been an insurmountable obstacle ...

"The thing is," Verrilli says, "you love who you love."

"I've been amazingly fortunate to have had the life that I've had," he adds.

The philosophical tone of that answer still belies Verrilli's emotional nature.

To better gauge that, a more direct question seemed in order: What makes him cry?

With a sheepish grin, Verrilli admits, "almost anything, actually," even "a stupid movie or television show."

"In addition to trying to make sure that I'm angry only when appropriate, I have to work on being emotional only when appropriate, too," he says.

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