Kicking off the session, Chairman Adam Schiff (D-CA) rattled off completely fabricated account of a July 25 call between President Trump and Ukrainian President Volodymyr Zelensky, in order to analogize the interaction to a scene from a mafia drama. 

Schiff was later forced to apologize, calling it a "parody." 

During his testimony, Maguire insisted he is "not partisan" and "not political," saying "I have served and led through turbulent times ... My integrity has never been questioned until now."

The rare open hearing of the intelligence committee commanded Washington's political attention Thursday given the implications for the newly launched impeachment inquiry against Trump, related to the whistleblower complaint.

But at one point in the hearing, during a tense exchange with Rep. Eric Swalwell, D-Calif., about allegations in the complaint of a potential "cover-up" regarding the Ukraine call, Maguire pushed back by reminding the committee that the complaint was not based on direct knowledge.