Katrina Pierson said ex-FBI Director James Comey's testimony exposed "serious problems in the federal government."
Pierson, a former aide to President Trump's campaign, said Comey absolved Trump of wrongdoing in the form of Russian collusion and obstruction of justice.
She also said Comey "opened the door and exposed problems in the deep state," appearing to refer to revelations that the former FBI chief "leaked" a document to a friend in New York.
During testimony, Comey admitted to leaking information to a "friend" at Columbia University Law School, which was allegedly meant to spur the appointment of a special counsel for Trump.
Pierson said that incident was an example of the "deep state" acting without regard for the commander-in-chief.
Noting that Trump contradicted several points of Comey's testimony after the hearing, Clayton Morris asked whether the president understood the "gravity" of offering to testify under oath.
Pierson said Trump has always defended himself well and is "adamant" about his recollection of events.
"[Trump is] the same person that has been underestimated from the time that he entered the race," Pierson said.