Rep. Adam Schiff, chairman of the House Intelligence Committee, opened up about Robert Mueller’s “heartbreaking” lack of acuity in a forthcoming book, which includes revelations about the special counsel appointed during the Trump-Russia probe.

Mueller, now 76, was appointed special counsel in May 2017 after former President Donald Trump fired FBI Director James Comey. Although Schiff writes that he pursued Mueller to deliver his July 2019 testimony, the reality was “heartbreaking” to Schiff when he struggled to answer basic questions.