Extracted from Unmasking Monsters: How the hunt for New Zealand’s worst criminals changed policing forever by Chook Henwood. RRP $37.99. Published by Allen & Unwin NZ. Out 6 August.

IT WAS 1993, AND SOUTH Auckland was being terrorised by a serial rapist. As far as we, the police, knew then, he’d appeared suddenly  in February that year in Manurewa, which was part of my police patch. Later we found out that he’d already been offending for ten years. The long trail of misery he left behind was enormous.  His victims over the course of those years included 50 to 70 girls and women who were attacked in their homes. We called him ‘the Ghost’. His oldest victim was 47, and his youngest just 10 years old. Many victims were under 17. 

At the beginning of the hunt for the Ghost I was 41 years old and a detective sergeant. By then I had been investigating  murders, rapes and robberies and arresting perpetrators for years in South Auckland, my lifelong patch. As this investigation dragged on, however, with the weeks turning into months and the offending happening over and over again, our inability to catch this particularly hideous criminal was gnawing at me. 

Every new investigative initiative we tried met with yet another dead end. We struggled to get regular staff to prevent further rapes  and violence and to investigate the crimes that had already been committed, due to the pressure of our policing area, a more general lack of staff, and what appeared to be little understanding of the sheer volume of the ongoing, brutal trail of carnage. Initially, the commitment to the task by the hierarchy was also questioned. When we did get a permanent team together, even then we still couldn’t find this ghost prowling our streets. What would it take to catch this criminal? 

After over a year and a half of fruitless searching, the management team for the operation began to understand that the way we were  going about things needed to change. What we didn’t realise at the time was that the system we would develop — off our own backs and with little help and no advice from the upper echelons of policing — would change policing of stranger rapes and murders in this country forever. 

This was criminal profiling. Allied with scientific breakthroughs in identifying DNA left at crime scenes, along with novel computing systems, it gave us a tool for hunting and catching rapists and other violent offenders. We would build a ‘profile’ of the likely offender from a synthesis of his criminal past and his characteristic behaviour at a rape scene. By creating this profile  from past behaviour, we could search for the offender in the present. 

This change not only broke with policing convention and methodology at the time, but it would also alter the direction of the rest of my career. 

FOLLOWING OUR SUCCESSFUL HUNT FOR the Ghost and, shortly afterwards, the Lone Wolf, I was one of the very small team setting up and operating the Criminal Profiling Unit. At the  outset it had just three, sometimes two, members of staff, along with very important assistance from a computer guru and the scientists working with DNA at ESR (Environmental Science and Research). During my time there, between 1998 and 2007, we helped to resolve many of the stranger rapes in Auckland and around the country, both current and historical. 

Although I’m not a great fan of statistics, the following example is interesting. The most rapes ever reported in one year in New  Zealand was 1265 in 1993, the year we started Operation Park. The following year the number dropped to 509; the year after that,  to 435. There may have been many factors that influenced these figures, as they always do with statistics, but however superficial they remain dramatic. 

The homicides we attended around the country were generally high-profile cases. In some our squad was able to focus the inquiry; in others we had little influence one way or the other. Profiling is not a silver bullet that will influence the investigation process of all homicide inquiries, just an extremely useful tool, as this book will show. 

Our work benefited from the use of two databases in particular  — one which held the data of charged persons together with a coded offence type and their addresses at the time of being charged, and the other which held details of behavioural aspects of the crimes. The first was primarily used to generate geographic  and criminal profiles that we used to create suspect lists, which were used to great effect in a number of investigations. The second  helped us to link crime to crime, and crime to offender, through analysing similarities in (especially) rape behaviours. 

The CPU that we set up back in 1998 is now known as the Behavioural Science Unit. It currently operates with a team of five: a detective senior sergeant in the role of supervisor, two registered psychologists and three intelligence staff who manage the behavioural  database. In the wider police operation, sex squads work in all districts and include CIB (Criminal Investigation Branch) teams focused on either adult sexual assault or child protection. These groups are well resourced and ring-fenced from other operational work. There is a  strong training programme around interviewing — a crucial part of any investigation — including advanced interviewing streams for suspects, adult victims and child victims. The child protection  teams work out of multi-agency centres with wrap-around victim  support and social worker teams. Specially trained staff interview all victims, with the interview recorded on video and using open-ended  cognitive interview techniques. The attending police would have taken just a bare-bones preliminary notebook statement to guide the investigation until the all-important victim interview could take place. 

Court practices have changed, too. Victims are assessed for vulnerability, and often their video interviews are played as their evidence. Some cross-examination may take place, but this is often done remotely via a video link so that the victim cannot see the accused and is sitting somewhere comfortable where they have support people. On occasions when victims are physically present in court, the old-school partitions are put up so they cannot see the accused and vice versa. Trials are now very victim-orientated; court services for victims (CSV) staff employed by the Ministry of Justice will manage the logistics of getting each victim up into the courtroom via a safe route. 

PLAYING A ROLE in identifying, charging and convicting rapists meant we were taking a sociopathic and brutal person off the street for many years and preventing more innocent lives from being destroyed. The work felt very meaningful; it was satisfying to know that we were making a long-term difference to the safety of women and girls, as well as giving victims a measure of closure. The number of criminals who become or develop into serial rapists isn’t high. The 30 or 40 rapists, including Joseph Thompson and Malcolm Rewa, whose cases we processed were responsible for a great percentage of all the stranger rapes. Some others we hadn’t personally dealt with, but the details of their crimes were now in our databases. We could study their behaviour and know our enemy. 

It was a time of great change, and I was fortunate (and proud) to be in the right place at this pivotal moment — and up for the challenge. 

Unmasking Monsters: How the hunt for New Zealand’s worst criminals changed policing forever by Chook Henwood was released 6th August 2024.