The day Helen was raped it was cold. She remembers exactly what she was wearing when her ex-boyfriend knocked at the door, wanting to come in. It was the same thing she always wore while studying at home in winter - a hooded sweatshirt, trackpants, socks.
"Why are you here," she asked. They'd broken up about a week earlier, after a short relationship. He'd been mean and controlling. She had two young children. She decided it was never going to work.
Unfortunately, her ex didn't see it the same way. He'd been texting her incessantly since the break-up, and now he wanted to talk in person, he said. He was quite aggressive about it. Reluctantly, Helen let him in.
Three years on, she still has flashbacks to the assault - of him pushing her down, the pain. Afterwards, while collecting her youngest child from kindergarten, she broke down crying. The teacher advised her to call the police, but all Helen wanted was a shower. Standing sobbing under the water, she scrubbed her thighs so raw the skin came off.
When she phoned the police that night, they booked a medical check straight away. Doctors were able to collect DNA the next day. The bruises on her legs matched where her attacker had forced her against the metal bed. She had other, internal, injuries as well. Detectives examined her bedding, her clothes. Helen gave a long video interview.
Police believed her, Helen says. But her case never got to court.
During questioning, the man's lawyer said they planned to argue Helen had opened the door in skimpy clothing, that she seduced him. They also wanted to use her sexual history against her, the fact that she had two children to two different fathers, one at age 19.
With DNA effectively ruled out because of the recent relationship, the case would largely come down to Helen's word against her attacker's, police told her. By then, Helen was suffering from post-traumatic stress disorder, including anxiety and insomnia.
"I was struggling mentally. Police thought I would be a mess in court," she says. "They thought I would be too weak ... and that we would lose."
Lacking the necessary evidence, police closed the file. Somewhere out there is Helen's assailant, an untried rapist. In official statistics, her case is considered "unresolved".
Helen's story is not isolated.
A Herald investigation found 2400 reported violent sex crimes went "unresolved" in 2016. Each unresolved case means police believe an assault occurred, but an offender was never charged and taken to court for that crime.
Since 1994, official data says almost 14,000 aggravated sexual assaults in total were unresolved. However, the Herald can reveal that, because an unknown swathe of sex crimes were categorised in a way that meant they were effectively removed from statistics, the true number of unresolved cases over the past 25 years is likely to be thousands more.
According to current police data analysed by the Herald, as of 2016 up to 80 per cent of reported aggravated sexual assaults go unresolved. For the crime "male rapes female 16 and over", that number is even higher, at 85 per cent. Rape cases are four times less likely to go to court in comparison with other types of physical assault, where only 24 per cent of offences are unresolved.
Official statistics say the rate of unresolved violent sex offences is higher now than at any time since records began. For most of the 1990s, and early 2000s, the unresolved rate hovered around 55 per cent. But after 2007 the rate began to climb and climb, so that when plotted on a graph the data looks like the steep, jagged rise of a mountain incline. The empty space below the incline represents 13,914 victims left in limbo, their stories unheard, their attackers untried.
On the face of it, one could assume the driver behind the spike in unresolved cases was the overall increase in reporting rates. Data shows reporting has also climbed steadily since last decade. But while more reporting might account for some of the upward swing in unresolved cases, it doesn't tally with such a sharp, rapid change. Instead, the more likely explanation is that the true rate has simply been misreported all along.
During its investigation, the Herald discovered that historic police data on sex crimes is deeply misleading. For at least 20 years since collection began in 1994 police were incorrectly coding some sexual assaults as "no crime". Where cases had limited evidence, or victims were intoxicated, or consent was unclear, instead of recording the incident as a "K6 - crime reported" police would instead label it "K3 - no offence disclosed" or "no crime".
Documents released by police to the Herald after Ombudsman intervention suggest the inappropriate use of the "no crime" code in upwards of 15 per cent of cases. Not only did this distort crime statistics to seem as though fewer sexual assaults were being reported, but it kept the "unresolved" rate artificially low for years, because K3 cases disappear from official counts.
Worse, because the catch-all K3 code was also used for the small minority of fake claims, academics say it led some police officers to conflate the two totals, resulting in the incorrect belief that a huge proportion of women were liars, and not to be trusted.
Police documents show the K3 practice continued despite Victoria University criminologist Jan Jordan highlighting the issue in a 2004 research paper, and the issue arising again in a 2009 study for the Ministry of Women's Affairs. In fact, while its use began to decline after 2007, the inappropriate use of K3 wasn't acknowledged by police until 2013, when an informal review was commissioned into 279 sex cases coded "no crime", in which the reviewer said its overuse should cease immediately.
According to the Herald's findings, the inappropriate use of the K3 code means that in addition to the thousands of people with official "unresolved" cases like Helen's, there could have been at least 2300 more men and women from the 20 years to 2014, who, despite reporting aggravated sexual assaults to police, never had it recognised they were a probable victim of a sex crime. If you include non-aggravated sex assaults as well - which the Herald did not - that number would be thousands higher again.
"That confirms everything we've seen in the community," National Collective of Rape Crisis spokesperson Andrea Black says.
"It's left so many people traumatised. People end up taking sides, saying 'she lied because police aren't investigating, she's crazy, she's chaotic.'"
Read more: How police disappeared thousands of sex crimes
Police, who have spent the past 10 years improving the way they deal with sexual assault following a Commission of Inquiry into Police Conduct, say they are no longer coding sex crimes they can't resolve otherwise as "no offence". Just 3.8 per cent of adult sexual assault cases designated K3 in 2017, police said.
Jan Jordan, who recently reviewed three months of police files from 2015, say her preliminary results suggest detectives are now truly reluctant to use the code for reported sex crimes. Compared to 2004, files are much more detailed, with more work put in before any decisions about prosecution are made, Jordan said.
Additionally, police have introduced a new recording system, with codes for outcomes such as "not pursued" or "investigation suspended", allowing officers to add nuance when they close a file, and for more detail in official data sets. They have also educated investigators about compliance with reporting standards.
What that all means, is that for the first time, we are probably seeing an accurate picture of the true rate of unresolved sexual assault cases in New Zealand.
It comes amid a sea-change moment for the campaign against sexual violence, where dozens of women have named their high-profile abusers as part of the #MeToo movement, where judges who blame victims will have their rulings overturned, and where the stigma and shame of sexual violence is being replaced with a mood of empowerment and change.
Much of the current debate centres around low reporting rates, and the need for victims to come forward, to follow the right channels, to be brave. However, what the Herald's investigation has found is even when victims do the "right thing" there is a very low chance their attacker will even get to court, let alone be convicted, despite police certainty their victims are telling the truth.
"The public awareness and international awareness is awesome but brings with it people who say I'm going to do something about my assault, I feel strong, society has changed... and then they go into that process and they wait in limbo," Black says. "They speak up and take action and then it's like: bam, stop, block, wait."
For women like Helen, it leaves a deep sense of frustration with the system that is supposed to help them.
"It's flawed," she says. "And that's why so many women don't go through with it."
"The detective said he believed me"
In New Zealand, the crime of rape carries a maximum penalty of 20 years' imprisonment. In terms of severity, it is second only to murder, and the most serious methamphetamine offices, on the sentencing scale. Unlawful sexual connection is the same. Between them, the two categories make up the majority of reported cases of aggravated sexual assault.
While some less serious offences are able to be resolved out of court, alternative resolutions do not apply to sex crimes. There are no warnings, no mediation. Rape either goes to court, to be heard in front of a jury, or it doesn't. Aside from the very small proportion of cases now deemed "no crime", almost all of the cases which don't make it are deemed "unresolved".
To find out why so many of New Zealand's reported sexual assaults do not reach court, the Herald spent six months speaking with victims, police, sexual violence advocates, lawyers, police and academics.
It reviewed studies and government reports, including Dame Margaret Bazley's 2007 Inquiry into Police Conduct, and the subsequent monitoring updates. It found the reasons cases aren't put forward for prosecution not only involve police practices, but in large part stem from inadequacies in the wider justice system, and the deeply entrenched views about rape still prevalent within society itself.
Ten years ago, it is almost certain that - fair or not - much of the blame for the unresolved cases would have been levelled squarely at police investigators.
However, sexual violence experts and advocates almost unanimously agreed that since Bazley's inquiry into police culture, there has a been significant change in the way police handle reported sexual assault.
The inquiry, commissioned after Louise Nicholas accused four police officers of rape in 2004, found major failings with the way police handled sexual assault cases, and a "culture of scepticism" about rape complainants.
It prompted an overhaul of police practice and policy, including better training, specialist sexual assault investigation teams, better communication with victims and more rigorous oversight of sexual assault files.
The changes were so widespread that the final police report, "A Decade of Change", released on the 10-year anniversary of the inquiry last year, ran to 40 pages. It covered each of Bazley's initial 47 recommendations, with specific details about each point.
For example, police noted they now have 105 trained investigators who specialise in investigating adult sexual assault complaints. In 2007, there were none. A "quality assurance" framework ensures files are audited both at district and national level. The K3 code was not mentioned in the report, although the Bazley inquiry is thought to have been partly behind the decline in its use.
The improvements have been noticed by victims as well as critics.
Grace, who was sexually assaulted as a teenager, said the first time she tried to report it to police in the 1990s, she was told her case would never get to court, and not to bother with a formal statement.
But when Grace complained again in 2015, prompted by news reports of allegations against high-profile entertainers such as Bill Cosby and Jimmy Saville, police doggedly tracked down her offender and charged him. While the charges were later dropped because of issues with the historic nature of the crime, she said the police had done a good job.
"The detective said to me, 'I believe you'," Grace said. "Even though there wasn't the outcome I wanted it was so much better that before, to be believed, to have [her abuser] put in a cell even for one night."
Victoria University criminologist Jan Jordan, one of the country's most experienced sexual violence researchers and an expert on police practice, said there had been a huge change in investigators' attitudes.
Her current study, a review of sexual assault files from 2015, was supposed to examine a year of case work, but she found the files so detailed she only needed three months' worth to see trends emerge.
While detectives still struggled at times with complex cases of intimate partner violence, or with victims who were intellectually disabled, they were much better at keeping an open mind, Jordan said.
"Cases which in the past would signal red flags, for example cases where victims were intoxicated, or suffered mental illness … police now suspend any judgement they might have while doing the investigation."
Jordan noticed discretion around decisions to prosecution were no longer in the hands of a single officer, and files were reviewed by more senior detectives. On several occasions, detectives were sent back to re-interview witnesses, in a bid to extract the most evidence possible.
"They really are trying a lot harder before making a decision on court," Jordan said.
A long process of generational change
Despite improvements, it is clear police are not perfect yet. Following publicity about the end of the inquiry's monitoring period last year, and the subsequent publication of a video series about "how to report a rape", a flurry of women came forward to complain to advocates and media about the way their cases were treated by police.
Rape Prevention Education executive director Debbi Tohill said five women approached her during May and June 2017 with complaints about unresolved sexual assaults. She passed their complaints to police.
Several more spoke to Stuff journalist Tony Wall, saying police hadn't tried hard enough to collect evidence, or had delayed work on their files.
Monique, a 22-year-old university student who complained to police that she may have been sexually assaulted in Dunedin, told the Herald she felt her case was one of those closed without enough investigation.
Records show that, at first, Dunedin police didn't even record her complaint as an offence, instead treating it as "information", which Monique believes was because she had limited memory of what had happened, and wouldn't use the word "rape".
"What had happened didn't match this idea that I'd been brought up to think what rapes looks like. My perception was only of violence, of stranger danger," she says. "My justification was it's just a bad experience, it's not that bad."
Monique laid the complaint after she participated in a blind date organised by the Otago University magazine Critic in 2016. The evening spiralled out of control, and Monique was so intoxicated she barely remembers getting to her date's house, or how she got into his room.
The first time she complained, police noted Monique "agreed" sex had been consensual, even though she says she doesn't believe it was. During university holidays, she complained again, this time at the Whanganui police station, where detectives did a full video interview - including 18 pages of handwritten notes - before referring the case back to Dunedin. The file was later closed as unresolved because of insufficient evidence, even though the Dunedin detectives didn't follow up advice from Whanganui to interview the taxi driver or get CCTV from outside the bar, or to talk to extra witnesses.
A lawyer who reviewed the file for the Herald noticed several clear red flags with Monique's file, such as her memory of climbing out a window at one stage, and saying "no" when asked for oral sex. Equally, her assertion she may have been anally raped was never looked into, after the alleged perpetrator denied it happened. Police also seemed to have delegated some aspects of the investigation - like interviewing the other men at the flat, some who allegedly exposed themselves to Monique - to the university proctor.
Police did not want to discuss specific issues about Monique's case, but said the investigation was "thorough" and it was reviewed appropriately. The university has since moved to set up a centre for sexual violence, and updated its sexual misconduct policy. Critic magazine now sends advice to students participating in the date to warn: "If your date is drunk, they cannot consent to sex. Any form of nonconsensual sexual contact is assault."
Two years later, Monique is still bruised by the experience with police, and suffers anxiety. Her graduation has been delayed twice. While the university has been flexible with her enrolment, its refusal to take disciplinary action against any of the students involved has added to her sense of trauma.
"My understanding is that there were no consequences from any of their actions ... because the police didn't lay charges," she says. "I just wish the Dunedin police had done a robust investigation. I wish that the Dunedin police had essentially treated me the way the Whanganui police had."
The sexual assault data analysed by the Herald shows that unresolved rates vary widely by district. For example, while the Southern district had 85 per cent of rape cases unresolved, Bay of Plenty had only 75 per cent.
Without going through each single file, it is very difficult to know if the discrepancies are because of the natural variation in cases, or if it is to do with flawed investigative practices. However, in its final report, the Office of the Auditor General (OAG), which was tasked with overseeing the 10 years of monitoring after the Bazley inquiry, also noted differences between police districts.
For example, some districts struggled to assign female investigators, and had higher levels of unassigned cases, it said. And while at a national level, there had been in improvement in compliance with policies and procedures for adult sexual assault investigation cases, the overall view hid the inconsistency in performance that existed among the districts.
Only 7 per cent of case samples at a national level failed to meet the threshold, it said, but the worst-performing district had about 20 per cent not meeting requirements. It would not release names of districts.
The OAG put much of the difference down to a generational shift.
"The victim advisers attribute some of this inconsistent quality of service to a minority of 'old school' investigators who may not have had specialist training in adult sexual assault investigation or have not put into practice that training," it said.
Andrea Black, from Rape Crisis, agrees with that analysis.
"There are still situations when victims walk in off the street after [an assault] that we understand meets the threshold for a crime and they're being told by either counter staff or police in communities that they need to just stay away from the person, and go to counselling rather than taking down the details and referring to specialist," she said.
Sometimes, decisions were based on the complication of woman's life and relationship or interaction with the person who assaulted them, or outdated views about alcohol and consent.
Overcoming some of those views was unlikely to be resolved by training alone, Black said.
"My stance has always been that it takes generations to change attitude, knowledge and skills - or police culture. It's a process of social change. It's personal, and those beliefs are deep in our families and our communities."
The police itself has noted there is more work to be done. In his foreword in "A Decade of Change", Police Commissioner Mike Bush wrote the report did not mark a finishing line.
"Our work doesn't stop here. We must continue to be vigilant and make ongoing advances ... because they are the right things to do in a progressive, relevant organisation, and the right things to do for the people who entrust us to serve them."
The evidential threshold: A hurdle too high
Police national headquarters is a grey, glassy building in Wellington's parliament precinct, near a motorway and the health ministry, largely indistinguishable from the other government agencies nearby.
In the cafeteria on its top floor, on a freezing day in July 2017, the Herald first meets national crime manager Tim Anderson and national sexual violence head Dave Kirby to discuss anomalies in the rape prosecution numbers. Later, Anderson alone answers questions by phone, with a public relations staffer also on the line.
Anderson, a detective superintendent with 25 years in the police, says two things are behind the increase in unresolved cases. First is higher reporting levels, which police believe comes from an increase in trust and confidence by victims of sexual assault. Second, he says, is the evidential threshold required by New Zealand's justice system.
For any criminal case, including a sexual assault, to go to court in New Zealand it must pass two tests: an evidential test, and a public interest test. To meet the evidential threshold required, the Solicitor General's prosecution guidelines say there needs to be enough credible evidence for there to a "reasonable prospect" a jury will convict.
Anderson calls the evidence test "the first hurdle", and the place where investigations are most likely to meet their end.
"Sometimes victims want to withdraw for different reasons. Sometimes people change their minds," he says. "[But] where a case is unresolved, generally it's because there's insufficient evidence."
Occasionally police are unable to identify an offender but, contrary to public belief, most cases are between people who already know each other.
Anderson says many unresolved cases would revolve around the issue of consent. In those cases, the only witnesses are frequently the two people themselves, and DNA evidence is largely unable to prove anything but that sex took place. After the investigation was completed, either the detectives themselves, or the police legal team, would review the evidence.
If it doesn't meet the threshold, police would then meet with the victim, and inform them of the decision. The case would then be closed, and the offender's name left on file in case more evidence was found or another complaint was made.
"It's still unresolved even though we have an undisputed idea of who the offender is."
The evidential threshold itself is not a scientific measure. In part it is dictated by recent experience of successful convictions. But because the conviction rate is also extremely low - 13 per cent - experts say it has a trickle-down impact on the prosecution rate.
When Jordan examined her sample cases last year, she noticed an increasing sense of disappointment among detectives where they weren't able to get cases across the line.
"I got the sense from comments on the file that the police were frustrated. Things like 'despite the impact on victim wellbeing and wish to see proceed, unfortunately threshold has not been reached,'" Jordan says.
"Unless an offender admitted it … they were left in limbo. It was really sad."
Anderson agrees - reluctantly - police were frustrated by the situation they found themselves in.
"Investigators work tirelessly, passionately," he said. "They get disappointed like any other human when they've toiled away at a certain case and the evidence has been there, or they believe the evidence has been there, and the outcome isn't what people expect."
Anderson said police were able to get some good results, and the country was lucky with the judges it had. However, his view was that many of the cases were not suited to New Zealand's "bruising" adversarial justice system, where opposing sides try to convince a jury their version of facts is most convincing, and which frequently seems to put the victim rather than the offender on trial.
"Me personally, I think the system isn't serving our victims well. That's my own view in terms of years of investigating these cases and thinking about this quite deeply."
While Anderson was expressing his personal opinion, it was clear from the Herald's investigation that many other officers felt the same way - and that in some cases it was influencing victims to withdraw.
Repeated victims said police warned them off going to court, saying their testimony or their sexual history would be torn apart under cross-examination on the witness stand.
Some victims said they appreciated the honesty. Others felt police were using it as an excuse not to prosecute. One woman was so terrified by a detective's description of the process she later refused to name her offender, scared she would be forced to testify if they found him.
Victim advocates said while the situation was less than ideal police often had the person who had been harmed at heart.
"They know it takes years," Black said. "They know it's painful and often further harmful to go through the court process."
"I'm not going to defend the status quo"
The failure of the justice system to deliver for victims of sex crime is not a new issue. While the Herald's investigation has revealed the true rate of unresolved cases, and the impact of the inappropriate use of the K3 code, the wider problems have been under discussion for a long time, with very little gained.
Successive reports have suggested solutions, the most recent a 2015 paper commissioned by former justice minister Amy Adams, called "The Justice Response to Victims of Sexual Violence: Criminal Trials and Alternative Processes".
The 2015 report's 82 recommendations included three major changes: including specialist sexual violence court pilot; establishing a Sexual Violence Commission to give victims more support; and offering an alternative justice process outside the criminal system if sexual violence victims preferred.
So far, only the sexual violence court pilot has been implemented. It will include the fast-tracking of cases, trained judges, and courtrooms with closed-circuit televisions. However, some say even if the pilot is successful, it will not be enough - largely because the decisions about conviction will still be made by a jury.
Canterbury University law professor Elisabeth McDonald, who is undertaking a study of the pilot courts, has discussed arguments that juries are not suitable for rape cases because they were more likely to believe "myths and misconceptions" about sexual offending.
"A judge-alone trial is likely to be much shorter," she told the Herald. "There would be less time spent on cross-examination, and the judge may well feel more able to intervene where necessary. Such a process may mean victims wouldn't feel as re-traumatised."
Anderson, the police officer, agreed.
"What would help? I believe that in most of these cases - and defence lawyers would cry out in horror at this - I think judges or panels of judges that determine criminal liability of the suspects in these cases," he said.
"You could tinker around the edges of the system - there could be other things - but would that change biases brought by individual jury members? Probably not."
Anderson also suggested a shift away from the adversarial approach for sex cases entirely, to an inquisitorial model, where the judge instead leads a fact-finding hearing, such as in most cases in mainland Europe.
The model was suggested for New Zealand in a 2012 paper by the Law Commission, but was shot down by then Justice Minister Judith Collins.
Its main benefit, advocates say, would be to shift blame away from victims, resulting in reduced emphasis on the victim's demeanour and behaviour. It would shift instead to more offender accountability.
The most radical change proposed has been a change to the idea of "reasonable belief". That would mean, rather than the accused claiming there was a "reasonable" belief consent was given, they would have to justify why - answering questions like "how did you check?"
Kathryn McPhillips, executive director of the survivor's agency HELP, said the reasonable belief issue was at the core of most rape myths.
"People will argue, because she went into the bedroom he was allowed to put his penis inside her. When that's not right."
So far, the idea has stalled because it would reduce the burden of proof - the idea that the prosecution has to prove someone guilty - not that they have to prove their innocence.
However, McPhillips said just because ideas were radical or difficult, that didn't mean they should be off the table.
"We need to overhaul criminal justice system. It's inhumane. And right now, people are voting with their feet. Until we fix the system, it's going to continue to impact who reports."
The new Government has signalled it wants to make changes. It appointed Green MP Jan Logie, herself a survivor of sexual assault, as the Parliamentary Under-Secretary to the Minister of Justice, solely working on domestic and sexual violence issues.
Logie said she was not going to defend the status quo. ''We need to do better, and I am committed to doing better," she said.
"There are some positive initiatives underway but no one believes they're enough."
She expected to take recommendations later this year for a reform package. While there was no "one solution" or quick fix, she was committed to improving outcomes for victims, Logie said.
For women like Helen, however, any intended reforms will come too late. While she has tried to move on, Helen is still getting counselling for the mental health issues caused by her assault.
Sometimes, she sees her attacker around town. Twice, he's driven right past her house.
Helen can't stop him. When her file was closed as "unresolved", her protection order was cancelled. She wants him to just disappear. But her alleged rapist can do whatever he likes.
*Some names have been changed to protect privacy
Read more: Click here for source data and details of the analysis
Where to get help
To contact police, call 111
Rape Crisis NZ: 0800 883300 or for a local branch detail, visit http://www.rapecrisisnz.org.nz/
Words: Kirsty Johnston
Data: Chris Knox
Artwork: Phil Welch