Newsroom reporter Melanie Reid says she can back up the claims made against Jami-Lee Ross with texts, recordings, and email chains.
On Thursday morning, Newsroom released a report detailing claims reportedly made by four women accusing the outgoing National MP of being a narcissist who used "brutal sex" to "dig dirt" on others.
"It wasn't just them saying, 'Hey, this has happened.' I have, obviously, lots of back-up information, recordings, I have email chains, text messages," Ms Reid told RadioLIVE.
She told RadioLIVE the allegations in the article aren't new, as she's been working on the story for a long time.
"When he's come forward and talked about... his moral compass and being incredibly comfortable with his behaviour, it's become a tipping point for these women. Because they've been sitting on this for a long time and have said nothing."
Ms Reid began investigating Mr Ross when "a group of people" came to her about a year ago.
Newshub has contacted Mr Ross for a response to the Newsroom article. He declined to talk to Newsroom.
Listen to the full interview with Melanie Reid above.
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