By Casey Sullivan
NEW YORK (Reuters) - Robert Mueller III, who was the longest-serving director of the FBI since J. Edgar Hoover, is joining law firm Wilmer Cutler Pickering Hale & Dorr LLP, the firm said on Monday.
Mueller, 69, stepped down as FBI director in September after overseeing some of the country's biggest cases, including the 9/11 attacks and the bombing at the Boston Marathon last year.
Mueller was nominated by President George W. Bush to serve as sixth director of the FBI and took office in 2001 just one week before 9/11.
He reshaped the bureau from a traditional law enforcement agency to a threat-focused, intelligence-based national security organization, FBI Deputy Director Sean Joyce said at the time of Mueller's retirement.
WilmerHale, co-headquartered in Washington and Boston, has 1,000 lawyers and has practices in white-collar criminal defense, investigations and intellectual property. It has recently recruited a number of top lawyers from government.
In September, the firm hired Dan Berkovitz, general counsel of the U.S. Commodity Futures Trading Commission between 2009 and 2013, and Mark Cahn, general counsel of the Securities and Exchange Commission between 2011 and 2012.
Robert Novick, co-managing partner of WilmerHale, said in a statement that Mueller's strengths were in dealing with "the hardest criminal justice matters (and) national security issues, including cyber-security threats."
Mueller could not be immediately reached for comment.
A 1966 graduate of Princeton University, Mueller joined the U.S. Marine Corps and served as an officer for three years, leading a platoon in Vietnam. He was awarded the Bronze Star, two Navy Commendation Medals, the Purple Heart and the Vietnamese Cross of Gallantry.
He earned his law degree in 1973 from the University of Virginia School of Law and later worked as a federal prosecutor in San Francisco, Boston and Washington.
(The story corrects spelling of WilmerHale co-managing partner's last name in seventh paragraph.)
(Reporting by Casey Sullivan; Editing by Ted Botha and Jeffrey Benkoe)