FBI confirms Mueller investigation reviewed James Comey's notes about his meetings with Trump
FBI Director James Comey in the Oval Office on September 17, 2013. Photo by Pete Souza

On Monday, a secret court filing was revealed showing that former FBI Director James Comey acted as a witness in special counsel Robert Mueller's investigation of Russian interference the 2016 presidential election — and that Comey's personal notes and memos documenting his meetings with President Donald Trump were "of interest to that investigation."

The details of the filing were revealed by USA TODAY editor Brad Heath:

As Heath noted, the filing also reveals that the memos revealed other witnesses to Comey's conversations with Trump. The memos, as well as the transcript of hearings the FBI held with judges, remain concealed from the public.

Comey, who was fired by Trump shortly after he demanded "loyalty" from him, has long been a key focus of the debate into whether the president obstructed justice during the course of the Russia probe. Attorney General William Barr's summary of the Mueller report claims that the special counsel neither charged nor exonerated the president — and some members of Mueller's team say that the full report includes evidence the president committed obstruction.