Special counsel Robert Mueller expected to be formidable against President Trump

Robert Mueller, the man recently appointed as special counsel in the investigation into Russia, is expected to be a formidable figure, even against President Trump.

In fact, a Slate report states that "it's almost certain Mueller and his team will end up asking Trump questions he doesn't want to answer and demanding to see documents he doesn't want to provide."

His appointment was announced on Wednesday amid calls for an independent investigation into possible ties between Trump associates and Russia which grew after the president fired FBI director James Comey.

Former FBI Director Robert Mueller

Mueller is said to be respected by both major parties, with a background as a Marine Corps veteran, federal prosecutor, and 12 years as FBI director, notes Reuters.

He was notably appointed to the latter position by former President George W. Bush and took office just before the 9/11 terrorist attack.

SEE ALSO: Sources: Trump campaign had at least 18 undisclosed contacts with Russians

In his role as special counsel, CNBC says that "Mueller and his staff can interview witnesses, subpoena documents and, if the evidence merits, work with the bureau to bring criminal charges."

While he is isn't required to keep the Justice Department informed about his team's work, some Democrats have raised concerns about his autonomy; House Minority Leader Nancy Pelosi has said, "Director Mueller will still be in the chain of command under the Trump-appointed leadership of the Justice Department. He cannot take the place of a truly independent, outside commission that is completely free from the Trump administration's meddling."

Meanwhile, concurrent Russia-related investigations in the Senate and House are expected to continue.