Story highlights Mueller is the second-longest-serving FBI director

He was former FBI director James Comey's predecessor

Washington (CNN) The Justice Department on Wednesday named Robert Mueller as special counsel to oversee the department's investigation into Russian meddling in the 2016 election. The former FBI director has a long history with investigations and prosecutions.

Mueller was former FBI director James Comey's predecessor. President Donald Trump fired Comey last week.

The longtime litigator was the second-longest FBI director in history, only behind iconic and controversial director J. Edgar Hoover. Congress passed legislation in 2011 to extend Mueller's term from the usual 10 years, giving him a 12-year tenure.

Mueller, 72, oversaw the FBI from September 4, 2001, just days before the September 11, 2001, terrorist attacks, until September 4, 2013.

Mueller is widely seen as a nonpolitical, dogged investigator, respected on both sides of the aisle. The extension of his term passed the Senate 100-0, and he was also initially confirmed in 2001 unanimously, 98-0.

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