Mueller, the former FBI director and special counsel, had been subpoenaed by the House Oversight Committee as part of an investigation into Jeffrey Epstein.

The former special counsel was diagnosed with Parkinson’s disease four years ago, Mueller's family told the New York Times in a statement on Aug. 31.

The former special counsel, who led the Russia investigation during President Trump’s first term, has had difficulty speaking in recent months. A congressional committee dropped a…