The two women who helped alter the course of American legal history by staging an impromptu protest in a Washington elevator have said they were driven by memories of private trauma and inspired by the courage of Dr Christine Blasey Ford.

Ana Maria Archila and Maria Gallagher of New York loudly berated Senator Jeff Flake for planning to back Brett Kavanaugh’s nomination to the supreme court on Friday, influencing him to alter his view and call for an FBI investigation, which the White House then ordered.

Kavanaugh, 53, is accused of sexually attacking Ford 36 years ago. He denies the accusation. In his own testimony to the Senate judiciary committee on Thursday, he angrily rejected the allegation as a political attack by Democrats. Ford testified prior to Kavanaugh, capturing the attention of a nation.

After their moment in the spotlight, Archila and Gallagher spoke of their personal motivations for cornering Flake in the Senate offices. Gallagher, a 23-year-old from Westchester, New York, said she had never told anyone about the assault she suffered. Archila, a 39-year-old from Queens, has disclosed that she was assaulted at the age of five.

Speaking to the BBC, Archila said she wanted Flake to “feel my rage”, as she believes “Judge Kavanaugh is dangerous for women”. On Saturday, she spoke to the Guardian.

“As we were waiting outside [Flake’s office],” she said, “we found out he put out a statement to support the nomination of Brett Kavanaugh. One or two minutes later he stepped out of a nondescript door.

“He was rushing to the elevator, we were running behind him. I was really still kind of in reaction mode to the announcement he had made with his statement. I had somehow pinned my hopes on him.”

Flake will retire from the Senate in November. Though he is a prominent critic of Donald Trump, he is also a strong conservative. Kavanaugh’s nomination would shift the supreme court firmly to the right.

“His statement made me deeply sad, deeply angry, frustrated,” Archila said. “So when he came out, I didn’t have anything planned to say. I just said I was here just a few days ago, telling my experience.”

Archila is a co-director at the Center for Popular Democracy (CPD), a not-for-profit group that campaigns for an “inclusive, equitable society”. She and Gallagher have been hailed as heroines by Democrats and by international supporters of the #MeToo movement.

Archila said she confronted Flake “because I recognized myself – I saw myself in Dr Ford’s words, and the way she told her story. We need to be believed. We wanted him to feel to have to look us in the eye to feel our pain. I thought, ‘We have to fight up until the last minute.’”

Archila had never told her story publicly, and in fact had to text her father to reveal the assault after she confronted Flake.

“I said, ‘You’re going to see something in the news, and I’m OK,’” Archila said.

“I was trying to protect him from my pain, from having to experience the pain. I was both incredibly sad that my fear as a child was in fact confirmed, but also [it was] kind of a relief that finally we could just hold it together, and I was able to say to him it wasn’t his fault, and it wasn’t my fault, and I felt very supported.”

Gallagher said her her mother called after seeing her protest on television. The family conversation to come would not be easy, Gallagher said.

Archila said she acted out of “shock and outrage at the possibility of someone being accused of attempted rape being in the supreme court” but also because “like women across the country” she was “offended by the fact we were being treated as unreliable, treated with disbelief, treated with doubt”.

Of Flake’s call for an FBI investigation, she said she was “honestly surprised”.

“He made a decision that seemed to be shaped by the moment,” she said. “I had a little seed of optimism, but I was really reminded: yes, this is how social change happens in these countries. People do things they’ve never done before.”

Gallagher tweeted that she was relieved to learn Flake had “heard their voices”. “We absolutely need an FBI investigation and for him and all senators to vote NO,” she wrote.

Archila also spoke to the BBC’s Newsnight. Asked if she thought it was their efforts that had led Flake to change his mind, she spoke of the outpouring from all those who had come forward to tell their stories.

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