Steve Bannon has been spending a lot of time with Robert Mueller

News about the special counsel investigation into the Trump campaign’s ties to Russia has died down in recent days, but we know Robert Mueller works quietly, and it turns out he’s just hit a major target: Steve Bannon.

Behind the scenes, Mueller’s team has spent about 20 hours this week talking with Bannon, the president’s former chief strategist, NBC News reports.

Bannon’s been in political exile since early January, but he was at the center of the action for about a year, running Trump's campaign for several months and bringing the victory, and then working in the White House as a key adviser present for some of the young administration's most controversial moments. It came to an end in August when he was forced out of the White House amid disagreements with other senior officials, and he has had a rocky public relationship with Trump since — especially over the "Fire and Fury" book.

Though it’s not known what he told Mueller, Bannon was part of the senior leadership of the campaign and administration for these key moments in focus in the Russia investigation:

• The March 2017 firing of former FBI Director James Comey, who says Trump demanded his loyalty and asked the FBI to drop its investigation into former national security adviser Michael Flynn.

• Flynn, who’s now cooperating with Mueller as part of a guilty plea, resigned last February after lying to the FBI and misleading Vice President Mike Pence about his conversations with Russia’s then-ambassador regarding sanctions during the transition process. Bannon was a top official on the transition team.

• The Trump administration’s public statements about a 2016 meeting between campaign officials and Russians promising dirt from the Kremlin on Hillary Clinton. President Trump oversaw the drafting of a misleading statement about the meeting that said it didn’t concern campaign issues. This proved false, as emails showed that Donald Trump Jr. agreed to meet on the pretext of receiving the damaging information.

Quoted in Michael Wolff’s “Fire and Fury,” Bannon also called the June 2016 Trump Tower meeting “treasonous” and accused presidential adviser (and son-in-law) Jared Kushner of money laundering.

Bannon has since apologized for the comments about the Trump Tower meeting, but Mueller surely won’t ignore the quotes.

Neither will Congressional investigators on the House Intelligence Committee, who spoke with Bannon Thursday as part of a weekslong process of interviewing him for their separate Russia investigation. Associates of Bannon report he’s ready to “tell all to Mueller,” but committee members told Politico on Thursday that Bannon’s responses to their questions were extremely limited and “scripted” by the White House. They’re considering a contempt of Congress motion.

Bannon’s decline has been swift since leaving the White House. He stepped down as executive chairman of Breitbart News in January after drawing intense scrutiny on the right for criticizing the Trump administration, comments which cost him the support of the Mercer family, billionaire GOP donors who had previously backed Bannon.

Cover image: Steve Bannon, President Donald Trump's former chief strategist, arrives for questioning by the House Intelligence Committee as part of its ongoing investigation into meddling in the U.S. elections by Russia, at the Capitol in Washington, Thursday, Feb. 15, 2018. (AP Photo/J. Scott Applewhite)