Veteran FBI agent Peter Strzok on Thursday rejected accusations of anti-Trump bias in his work on the Russia collusion probe, telling lawmakers that attacks on the FBI and Justice Department were a "victory" for Vladimir Putin.
In a fiery Congressional hearing that broke down into partisan shouting, Strzok told lawmakers that his comments in private text messages to his lover, FBI lawyer Lisa Page, were a reaction to Donald Trump's "horrible, disgusting behavior" on the 2016 campaign trail.
But he denied that his personal beliefs had influenced his professional judgment and warned the House Judiciary and Oversight Committees that Republican attacks on his agency and the DoJ only served to divide the American people.
"This investigation is not politically motivated, it is not a witch hunt, it is not a hoax," Strzok said.
"I have the utmost respect for Congress's oversight role, but I truly believe that today's hearing is just another victory notch in Putin's belt and another milestone in our enemies' campaign to tear America apart."
Trump has dubbed Strzok and Page the "FBI lovers" -- and used their messages to tar the FBI with allegations of bias, and undermine the probe into whether his campaign team and Russia colluded to influence the election.
Strzok said his opinions did not influence his work on the Russia probe or the investigation into the use of a private email server by Trump's 2016 election rival, Democrat Hillary Clinton, during her time as secretary of state.
"Like many people, I had and expressed personal political opinions during an extraordinary presidential election... opinions that were not always expressed in terms I am proud of," he said.
"But let me be clear, unequivocally and under oath: not once in my 26 years of defending my nation did my personal opinions impact any official action I took."
Tens of thousands of text messages between Strzok and Page sent during their 2015-2017 affair have been made public, revealing coarse comments denigrating Trump both during and after the 2016 election.
Republicans have seized on the texts as proof that the FBI is too riddled with bias to fairly investigate Trump.
"A bias-free investigation is not a Republican or Democrat issue -- it's an American issue," said Republican Representative Trey Gowdy.
Gowdy latched onto several comments made by Strzok -- calling Trump an "idiot" and worse, and a pledge to a distressed Page in August 2016, just as the FBI began investigating links between the Trump campaign and Russia, that the real estate mogul would not become president.
"No. No he won't. We'll stop it," Strzok told her.
Strzok said the comment was a response to Trump's actions on the campaign trail.
"You need to understand that that was written late at night off the cuff, and it was a response to a series of events that included then-candidate Trump insulting the immigrant family of a fallen war hero," Strzok told the panel, sparking a burst of applause from the audience.
It reflected, he said, "my presumption, based on that horrible, disgusting behavior, that the American population would not elect someone demonstrating that behavior to be president of the United States."
The open hearing, coming two weeks after the same body interviewed Strzok for 11 hours behind closed doors on the same subject, was in part televised political theater that Republicans hoped would erode public trust in the ongoing Russia investigation.
Trump -- who also faces allegations that he tried to obstruct the probe -- has singled out Strzok and Page as representative of the deep prejudice against him in the US justice system.
"How can the Rigged Witch Hunt proceed when it was started, influenced and worked on, for an extended period of time, by former FBI Agent/Lover Peter Strzok?" Trump tweeted ahead of Thursday's hearing -- one of half a dozen posts on the topic in the past four days.
"Read his hate filled and totally biased Emails and the answer is clear!"
Judiciary Committee Chairman Bob Goodlatte threatened Strzok with contempt of Congress for refusing to answer questions on specifics of the Russian investigation -- on the instruction of FBI lawyers.
That sparked blasts against Goodlatte and a push to shut down the hearing by Democrats, who said Strzok was placed in an impossible position.
Strzok said the accusations of bias are "deeply destructive" to the FBI's mission, insisting the agency's management structure prevented anyone's political views from tainting its operations.
"They would not tolerate any improper behavior in me any more than I would tolerate it in them. That's who we are as the FBI," he said.