The special counsel and federal prosecutors in New York will have to file separate memos in court detailing the cooperation of longtime legal fixer of President Donald Trump, Michael Cohen, who has admitted lying to Congress.
Mueller's team will also be disclosing what they claim former Trump campaign chairman Paul Manafort lied about when his plea deal fell apart last month. Manafort has claimed Mueller is forcing him to lie, and has refused.
The court filings will close out a week in which Mueller's team for the first time provided some details of the help they've received from former Trump national security adviser Michael Flynn.
Prosecutors also disclosed that he had cooperated not only with the Russia investigation but also with at least one other undisclosed criminal probe.
Mueller's team said Flynn's assistance was "substantial" and merited no prison time.
The new details about Mueller's investigation are set to become public as Trump continues to lash out at the expensive, long running probe. Trump singled out Cohen, accusing him of lying to get a reduced prison sentence. The president also praised another associate, Roger Stone, for saying he wouldn't testify against him, and Trump said a pardon for Manafort isn't off the table.
In the latest filings Friday, prosecutors will weigh in on whether they believe Cohen deserves prison time and, if so, how much. In doing so, they'll have to provide a federal judge with at least some description of the assistance he's provided to their investigations — the Russia probe and a separate investigation led by the U.S. attorney's office in Manhattan.
In August, Cohen pleaded guilty to eight criminal counts, including tax evasion and campaign finance violations.
None of confessed crimes were related to Russian meddling in the 2016 presidential election.
Cohen admitted he lied about the details of a proposed Trump Tower in Moscow, saying that talks about the project went on until June 2016 — longer than he previously said. Trump has downplayed the project and stressed that he never put any money into the deal and ultimately decided not to do it.
In Manafort's case, prosecutors are expected to lay out what torpedoed the cooperation agreement he made when he pleaded guilty in September to two felony charges of conspiracy against the United States and conspiracy to obstruct justice.