O'Melveny & Myers is beefing up its U.S. Supreme Court and appellate practice with the addition of Stanford Law School professor Jeffrey Fisher, one of the most frequent advocates at the court, as special counsel.

The firm is set to announce Monday its new relationship with Fisher, who will maintain his position at Stanford and as co-director of its Supreme Court clinic, a position he's held since 2006.

The 47-year-old Fisher has argued 35 cases before the high court, including three this term that are pending decisions. Known for his straightforward advocacy, Fisher has argued both criminal and civil cases in his capacity as a Stanford professor and in prior private practice at Davis Wright Tremaine. He was co-counsel in the Kentucky case that was part of the same-sex marriage litigation at the Supreme Court in 2015.

Among his other notable cases was the 2007 Exxon Valdez oil spill case Exxon Shipping v. Baker, in which his adversary was O'Melveny partner and former acting U.S. Solicitor General Walter Dellinger.

“Jeff was terrific. He is one of the best lawyers to work with and to have as an adversary,” Dellinger said in an interview. Negotiations to bring Fisher on board at O'Melveny have been going on for several months, Dellinger said, but “my aspirations [to engage Fisher] go back a long ways. Jeff is a spectacular addition to our appellate practice.”

Jonathan Hacker, chairman of O'Melveny's Supreme Court and appellate practice, has known Fisher for nearly 20 years. “His commanding advocacy skills are matched by his personal warmth and charm,” Hacker said in a statement. “He will connect with our colleagues and clients as easily as he connects with courts.”

Hacker and Fisher have been longtime members of the National Association of Criminal Defense Lawyers amicus curiae committee. Fisher is a former clerk to Justice John Paul Stevens and the late Ninth Circuit Judge Stephen Reinhardt.

Dellinger said Fisher will bolster the practice after some of its key members, including Sri Srinivasan, Pamela Harris, John Owens and Goodwin Liu, left O'Melveny for appellate judgeships on the D.C. Circuit, the Fourth Circuit, the Ninth Circuit and the California Supreme Court, respectively.

In an interview, Fisher said he was drawn to O'Melveny in part because of its “great commitment to pro bono work.” He said he got to know and like Dellinger during the “hard-fought” Exxon Valdez case.

In addition to “pitching in” on O'Melveny cases, Fisher said the firm may assist the Stanford clinic on pro bono cases that come to the clinic, especially during the summer when it is not operating with a full complement of students.

Fisher burst onto the Supreme Court scene in 2003 and 2004 with arguments in two groundbreaking criminal cases—Blakely v. Washington on sentencing, and Crawford v. Washington on the confrontation clause. He was a fifth-year associate at Davis Wright at the time. He won both cases in decisions authored by Justice Antonin Scalia. In 2006, The National Law Journal named him one of the nation's 100 most influential lawyers.

After Fisher took on Exxon Shipping in the 2007 Exxon Valdez case, Slate's Dahlia Lithwick gave Fisher a different kind of accolade: “In addition to having the best hair of the Supreme Court appellate bar, he is also one of its coolest new additions.”

Asked about the hair compliment last week, Fisher said with a laugh, “I don't know if that was a favor or a curse.”

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