Who is Robert Mueller?

Since being tapped to investigate the Trump campaign's ties to Russia, Robert Mueller has been praised by both parties for his fierce independence

Former FBI Director Robert Mueller in 2013. Mueller has been named special counsel to lead the Trump-Russia probe (Larry Downing/Reuters)

Former FBI Director Robert Mueller in 2013. Mueller has been named special counsel to lead the Trump-Russia probe (Larry Downing/Reuters)

On Wednesday, former Marine and FBI director Robert S. Mueller III was appointed the special counsel to oversee the investigation into Russia’s interference with the 2016 U.S. election.

Mueller will pick up the investigation where James Comey left it before being abruptly removed from his post as FBI director on May 9. The decision to appoint Mueller, made by deputy attorney general Rod Rosenstein, followed a week of increasingly bad optics around Trump’s decision to fire the man tasked with investigating his campaign’s ties to Russia. (“Do not ask me about how this looks,” one senior White House aid told a reporter last week, “we all know how this looks.”) Appointing a special counsel was largely seen as an attempt to restore the public’s trust in the Justice Department’s investigation.

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White House Republicans and Democrats alike welcomed the appointment of Mueller, who is leaving a position with WilmerHale law firm to take on the role of special counsel. The 72-year old New-Yorker served as FBI director from 2001 to 2013, during which time he built a nearly unscathed reputation as being fiercely independent and honest. Senate Minority Leader Charles E. Schumer (D-N.Y.) praised the appointment in a statement saying: “Former Director Mueller is exactly the right kind of individual for this job. I now have significantly greater confidence that the investigation will follow the facts wherever they lead.” Peter J. Roskam of (R-Ill) called him “a man of the utmost integrity,” and Darrell Issa (R-Calif.) said Mueller was “somebody we all trust.”

The universal praise for Mueller means that whatever comes of the investigation will likely be deemed credible and true by both parties.

The appointment also comes as a relief to the FBI, which saw Comey’s firing as a bitter blow to the bureau. “The fact that the investigation is now going to be led by Mueller, who is so like Comey in so many ways and who also loves the bureau, is sweet justice,” one senior FBI official told Politico.

In his letter announcing the appointment, Rosenstein outlined Mueller’s authority in the Russia probe, including the power to investigate “any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump,” adding that if “necessary and appropriate, the Special Counsel is authorized to prosecute federal crimes arising from the investigation of these matters.”

Until now, the biggest challenge of Mueller’s career was arguably dealing with the aftermath of the 9/11 attacks, which rocked the U.S. just a week into his job as FBI director. The department was accused of not having done enough to prevent the attacks. And while the FBI was subject to a number of government investigations, the bureau ultimately came out intact.

Three years later, Mueller and Comey, then-deputy attorney general, would share the spotlight for the first time when they challenged President George Bush’s use of executive power. Both men threatened to resign if Bush continued his domestic wiretapping program that was deemed unlawful. Bush eventually conceded.

In a statement following Mueller’s appointment on Wednesday, Donald Trump doubled down on his message that the investigation will come up empty. “As I have stated many times, a thorough investigation will confirm what we already know: there was no collusion between my campaign and any foreign entity,” he said. “I look forward to this matter concluding quickly.”

Based on other investigations of this nature, and Mueller’s meticulous attention to detail, it’s unlikely the case will close quickly. In fact, it could drag out for years and potentially outlive Trump’s term as president.