Former FBI Director Robert Mueller was just appointed special counsel to investigate Trump and Russia

The Justice Department has appointed a special counsel to investigate Russian interference in the president election, according to multiple news reports.

Former FBI Director Robert Mueller, nominated by George W. Bush in 2001 and reappointed by Barack Obama in 2011, will oversee the probe into “the Russian government’s efforts to interfere in the 2016 presidential election,” according to a copy of the order posted by BuzzFeed.

Congressional Democrats have stepped up their calls for a special prosecutor to investigate Trump’s Russia connections, particularly since the president fired FBI Director James Comey last week. Deputy Attorney General Rod Rosenstein’s decision to tap Mueller — a career law enforcement officer with bipartisan credentials — is a big and unexpected step toward meeting their demands. ABC News is reporting that Trump’s White House was “blindsided” by the announcement and only notified about 30 minutes before the justice department went public with Rosenstein’s decision.

As special counsel, Mueller will have the legal authority to prosecute crimes. (An independent commission, which some Democrats have also called for, would not.) However, Mueller can still be dismissed at any time by Rosenstein, who can in turn be dismissed by Trump.

As Vox’s Jennifer Williams explained, the special counsel “is appointed directly by the attorney general (not an independent three-judge panel, like before) and — this is the important part — is thus directly answerable to the attorney general. This person can pursue criminal indictments in grand jury investigations, but the attorney general can fire them at any time and overrule any decisions they make when it comes to investigating or prosecuting the case.”

Still, the news will almost surely be welcomed on Capitol Hill as a necessary step toward a nonpartisan investigation into the biggest scandal currently dominating Washington.

“The American people’s trust in our criminal justice system is in Mr. Rosenstein’s hands,” Senate Minority Leader Chuck Schumer (D-NY) told reporters earlier this week. “This investigation must be run as far away from this White House and as far away as possible from anyone appointed by this president.”