“We welcome the appointment of a special counsel to investigate Russia’s meddling in our elections, a critically necessary step given the conflicts of interest present at the Trump administration’s highest levels.”

Since April, Mueller has been in charge of the distribution of almost $1bn to victims and automakers affected by Takata’s defective airbags. He also served as the NFL’s independent investigator into the league’s handling of a violent episode involving former Baltimore Ravens player Ray Rice.

At the time of that appointment, in 2014, Andrew Weissmann, a former FBI general counsel who worked for Mueller, said, “You’re not going to hire Robert Mueller if you’re looking for a whitewash.”

Indeed, few lawyers and government-focused law firms have built resumes as impressive as Mueller and WilmerHale when it comes to working for Democrats, Republicans and as independent counsel.

Mueller ran the FBI for for more than a decade. President George W Bush appointed him in 2001, a week before the 9/11 attacks. Though FBI directors have a 10-year tenure, President Barack Obama asked Congress to allow him to stay on another two years.

In recent years, WilmerHale has stocked up on former high-ranking US government officials such as Mueller for its ranks, including former Obama-era Deputy Attorney General David Ogden and a Bush-era ambassador to Germany, Robert Kimmitt.

Partner Reginald Brown, who worked in the Bush White House and runs the firm’s financial institutions group and congressional investigations practice, is advising Paul Manafort as of this spring. Manafort, who ran Trump’s presidential campaign for six months, may be ensnared in the Russia investigation because of a consulting client he represented in Ukraine who had ties to the Kremlin.

Top Clinton administration alumni at WilmerHale include former Solicitor General Seth Waxman and former Deputy Attorney General Jamie Gorelick, who has boosted her own resume in recent months by advising Ivanka Trump and Jared Kushner on government ethics.

In another connection, Hale and Dorr, the predecessor firm, once housed James St Clair, the lawyer who represented Richard Nixon during Watergate. Hale and Dorr merged with Wilmer Cutler Pickering in 2004.

National Law Journal reporter Marcia Coyle contributed to this report.