When Lauren Ingram posted the first of her tweets exposing the identity of her alleged rapist, it felt like "a little act of power and resistance" after two years of feeling like she was getting nowhere.

"I've talked about this before but not in detail," the 27-year-old Sydney journalist wrote in that first post. "So here is it: in April 2015 I was raped by a man who is a Greens member."

The man had been a friend of Ingram's. On the night in question, he invited her to his house, where what began as consensual sex turned into what she described as a violent assault.

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Ingram named him, tagging his username, in a later tweet.

While many applauded her bravery, not everyone agreed social media was the place to name and shame a man over allegations that had not been tested in court.

But Ingram was fed up with the official channels. For two years she had complained to the police and the NSW Greens, where her alleged rapist was employed — and felt she had been thwarted at every turn.

Police had lost interest in her case, she believed, and told her that her hospital records had been permanently destroyed, which would have made her case much weaker if it went to court.

But Background Briefing has discovered these files still exist — a revelation that Ingram said reinforced her decision to go public with her alleged attacker's identity.

Taking matters into their own hands

Ingram is part of a bigger movement of young women who are willing to take the law into their own hands in sexual assault cases.

Despite police warnings that public shaming could backfire, women across Australia are joining private Facebook groups that share stories about which men to avoid.

"I'm a part of the secret underground feminist mafia that tells all of my friends, and even just women I meet ... about who the bad guys are, who the rapists are," said Anna, a member of one group like this.

"The system isn't set up to help me. It's set up to help him. This is our own system."

Anna said she could think of five men she regularly told her friends to avoid. Even within the last month, she said, she'd cut a man out of her social circle after hearing about his ugly history.

It's this kind of warning that Sydney writer Erin Riley wishes she'd given Ingram.

A month before Ingram's alleged rape, Riley said she had a similar experience with the same mutual acquaintance: she describes initially consenting, before the sex turned violent and intimidating.

Riley didn't go to hospital after it happened. She didn't go to police straight away. For weeks afterwards, she went back and forth between denial and feeling deeply violated.

Now, she wishes she'd said something. "I felt so guilty. I felt like if I had recognised it and if I'd said something earlier, if I'd warned her…" Riley said. "I didn't."

Police warn of dangers of speaking out

Some described Ingram's move to go public as vigilantism. She doesn't totally disagree.

"It's almost like taking back the power, taking back whatever you can, to put against the system that isn't working," she said. "It's like a little act of power and resistance."

This reasoning troubles Detective Superintendent Linda Howlett, who heads the New South Wales sex crimes squad. At the end of the day, she said, it would not help get an offender arrested or charged.

"It could have had the potential to compromise the evidence that could be obtained," she said.

"The other thing we certainly don't want is for that social media comment to be out before a judge and jury, because it could place doubt on the actual circumstance the investigation or anything the victim might say."

And then there's the risk that the accused rapist could sue the rape victim for what they've said online.

"The victim could be leaving themselves open to civil prosecution by the offender who's actually committed the offence against them," Superintendent Howlett said.

"Until a person is actually convicted, they're innocent in the eyes of the law of that particular offence."

The night of Lauren's alleged rape

Over the course of her tweets, and in her interview with Background Briefing, Ingram laid out her account of what the man, who she had once considered a friend, did to her.

In one of her tweets, Ingram shared this image of bruises on her shoulders and neck. ( Twitter: Lauren Ingram )

The night began with him texting her, asking if she wanted to hang out at his house and eat pizza. When she arrived at his place, there was no pizza, but he'd bought some gin. Conversation led to kissing and then consensual sex.

But Ingram said it wasn't long before he started getting rough. When she felt him biting her, she told him it hurt and asked him to stop.

"I think I said stop four or five times, and he grabbed my arm and was holding me down onto the bed and just kept going," she said.

Then, she said, he hit her, and held her down on the bed when she tried to get up.

"I was terrified … fear and pain were the only things in my head. I'd never experienced anything like that before in terms of real fear," she said.

Going to the police

Ingram texted two of her girlfriends that morning to tell them what happened. They came over, saw her bruises, and urged her to go to hospital — so doctors could check she was OK, but also so there was evidence of what happened.

The hospital recorded the extent of her injuries. A couple of weeks later, Ingram gave her first statement to a police detective at Kings Cross station.

She remembers providing photos of her injuries and Uber records that showed when she arrived at her alleged attacker's house. She recounted her recollections of the night, including how many times she told him to stop.

At one point, she said, the detective taking notes described the accused man as "just a kid that doesn't know how to have sex yet". To Ingram, it felt like he was dismissing her complaint.

At a women's march in January this year, Ingram drew attention to her anger with police. ( Twitter: Lauren Ingram )

"I thought, if a police officer is going to say something like this to me, what is anyone else going to think?" she said.

"If this goes up in front of a jury, who is going to believe me, if a police officer who has seen all of this doesn't believe me?"

Superintendent Howlett told Background Briefing such a comment would not have been acceptable. She agreed with a request to investigate the claims.

"Give me the details, and I'll chase it up," she said.

A spokesperson for Superintendent Howlett has since replied, saying they've looked into the history of Ingram's case, but "detectives are not in a position to discuss the details of an ongoing investigation".

Let down by the justice system

Ingram's distrust of police and the courts is a common theme on the Facebook groups that aim to spread the word about alleged sexual predators.

Many women have heard of stories like Sarah Gatta's.

When Ms Gatta, now 39, was younger, she broke up with a boyfriend who didn't take it well — and said he wouldn't leave her alone until she came and saw him face to face.

But she said the morning she went to his apartment to confront him, he raped her.

"I said no, and I screamed and I hit him, and he restrained me … I just wasn't strong enough," she said. "When I left, I yelled at him, 'You raped me!' And he laughed at me and called me stupid."

She went to police, who made an application for an apprehended violence order (AVO). Within hours of the police serving the order, her ex-boyfriend phoned her. He was charged over the breach and taken to court.

In the end, police didn't press charges. Ms Gatta said she was told by prosecutors that this decision was based on a statement from a witness who claimed she was a liar and promiscuous.

Sarah Gatta lost all faith in the system after she accused her ex-boyfriend of rape. ( ABC RN: Tiger Webb )

Given a second chance

Sixteen years after her alleged rape, Ms Gatta got a phone call from a detective. Three other women had accused the same man of sexual assault, and police were mounting another case against him. They wanted her to be involved.

"I said: 'Absolutely, whatever you need me to do to bring this man to justice. He has to go to jail.'"

Sorry, this video has expired Sarah Gatta’s experience

But for the next three years, Ms Gatta was involved in a lengthy legal process, the trauma of which was exacerbated by the way she said police mishandled her case. She said police told her that her original statement from 1997 was accidentally destroyed together with the AVOs.

The statement turned up in her own searches with Victims Services, but the AVOs were gone — and Ms Gatta was instructed by her lawyer not to mention them in court.

Then she was advised that prosecutors would not be running all the cases together. Instead they were going to split them. The jury wouldn't hear about him allegedly doing this to other women.

A process that leaves victims scarred

What happens next is complicated: the first trial was aborted, and then there was a second trial. Ms Gatta was cross-examined in both. She was left feeling broken.

"You are a victim, but they don't treat you as one," she said. "There's little respect or compassion … I'm sitting there and describing this horrific tale, and it's so personal and intimate and gory and embarrassing, quite frankly."

In the end, the man standing trial for the rapes of three women was acquitted. Three separate trials failed to get a conviction.

Ms Gatta felt the police had sabotaged her slim chances of justice. She decided to put in a Freedom of Information request (FOI) to get her file and use it to lodge a formal complaint.

When she was notified her FOI had been successful, the email included a copy of the AVO she was told had been destroyed and could not be relied on in court. The whole process, Ms Gatta said, left her scarred.

"There's nothing the system provides right now that would ever tell me that it's a safe place for a victim to go," she said.

Superintendent Howlett from the NSW Sex Crimes Squad admitted policies and procedures "weren't that great" when Ms Gatta first went to authorities about her rape. But, she said, things had improved since then.

And she has advice for women in Ingram's position: "I know it's tempting to go on social media but it actually could end up backfiring on you."

"[If you're] a victim, please, please, I'm begging you — please come forward."

After a third visit to police, Ingram remains unconvinced the system will deliver her justice. ( ABC RN: Tiger Webb )

Driven by a 'need to say something'

Ingram is not only disappointed in the justice system — she also feels that the Greens, who employed her alleged rapist as a staffer, could have done more.

Background Briefing can now reveal the Greens began drafting a sexual harassment and assault policy specifically in response to complaints from a number of women about the same man's behaviour.

"I had gone to police, I had gone to the political party, and no-one had done anything, and no-one had stopped him," she said.

"And what I kept thinking about was this guilt, or this need to say something. Because I was so worried about him hurting other women."

And after her third time at a police station, speaking to a fourth investigator about her allegations, Ingram remains unconvinced the system will deliver her justice.

The second time she spoke to police, she was told her hospital records had been destroyed — making it more difficult to rely on her injuries as evidence if the case was to go to court.

But just as in Ms Gatta's case, these records were not in fact destroyed.

In a phone call with Ingram, the hospital sexual assault coordinator confirmed a record of her examination and her DNA samples still existed.

Ingram feels it vindicates her decision to name and shame her alleged rapist, even if her case never ends up in court.

"When it comes to rape victims … the burden of proof for someone who's been assaulted often results in men getting off, which means that then they can go and assault other women," she said.

"I understand that some people might think, oh, it's just an accusation. It is. But there's nothing I can gain from putting myself out there like this. I've already lost a lot."

UPDATE: The man in question has now responded, saying he denies all the allegations.

He wrote in an email that he believes that in Australia, justice is served through our established justice system and that it cannot be served through the "social media lynch mob".