How police used DNA to solve some of NZ's high-profile criminal casesby Donna Chisholm
Manning is the national ESR liaison adviser and police go-to person for advice on problematic DNA matters, cold cases and historical sexual assaults. With advances in DNA technology in the mid-2000s, Manning launched a project to re-examine stored exhibits from serious sex crimes between 1990 and 2000. The ESR had retained samples in 47 cases, and when they were reworked, 35 provided a meaningful profile. Of those, 20 linked to men who were already on the ESR’s databank, resulting in charges being laid and eight convictions. Twelve cases could not be progressed. The other 15 profiles, which didn’t match any known offenders or suspects, have now been loaded onto the crime-scene database and can be matched if the same men reoffend.
Manning says police try to target offenders and suspects from whom they expect the “biggest return”. “We want to get the young, active, high-volume offenders on the databank, because we know they’re the people who are likely to leave DNA at a crime scene in the future. There’s no point getting it from an 80-year-old grandma who does a bit of shoplifting.”
Manning was involved in the hunt for Auckland serial rapist Joseph Thompson in the mid-90s, when there was no law to compel a suspect to give a sample. “We had profiles from maybe half a dozen cases and knew we were looking for a serial offender. Joe was on our priority list, anyway [because of his criminal history and where he lived], and he was asked for a sample, but he kept putting it off. Finally, he agreed to provide a buccal [cheek] swab – he said he couldn’t give blood because he was a Jehovah’s Witness.”
About a dozen buccal swabs had been submitted to the ESR in the case before then, but none yielded a profile police could use. Although Thompson’s sample showed promising results early in the analysis, in those days it took three months to develop a full profile.
“Today, we can get one in 48 hours – that’s what we were fighting with. We thought the forensic science was wonderful, but in hindsight, it was bloody slow and cumbersome and slowed things down a lot.”
Police put Thompson under 24-hour surveillance while they waited for the results. “We had an ex-army officer in the police and he used to harness himself up a bloody tree, bring a sandwich and hang in there for a 12-hour shift.”
In July 1995, Thompson pleaded guilty to 129 charges, including 61 sexual violations of women and young girls, and was sentenced to 30 years’ jail. It was the first time DNA had been used to catch a serial rapist.
You’d expect shows such as CSI that showcase forensic science would deter some offenders, but there’s no evidence of it, says Manning. “For some reason, crims keep leaving their DNA at crime scenes and we keep finding it – and finding them.”
DNA evidence in high-profile cases: A timeline
DNA evidence is produced for the first time in a New Zealand court, when 18-year-old Michael Pengelly is convicted of the home-invasion murder of 77-year-old Beatrice Birch in West Auckland. The quality of the scientific analysis of what was allegedly Pengelly’s blood at the scene is questioned by his lawyer, Murray Gibson, supported by the “father” of the technology, UK professor Dr (later Sir) Alec Jeffreys. Six years later, Gibson and scientist Arie Geursen use re-analysed DNA evidence to free wrongly convicted child-rape accused David Dougherty.
Scott Watson is convicted of murdering Ben Smart and Olivia Hope in the Marlborough Sounds on January 1, 1998. The only physical link between the couple and Watson is ESR evidence that two blonde hairs recovered from a blanket on his washed boat were highly likely to have been Olivia’s. The evidence is still being contested.
Jules Mikus is found guilty of murdering Napier schoolgirl Teresa Cormack, who was abducted and killed in 1987, after DNA swabs from her body were retested using new technology.
Jarrod Mangels admits the 1987 murder of Maureen McKinnel in Arrowtown after DNA found under her fingernails was retested. Mangels was just 15 at the time of the killing.
DNA from a single strand of hair found at the scene of the murder of 66-year-old Tokoroa teacher Lois Dear is traced to 23-year-old Whetu Te Hiko, who pleads guilty in February 2007.
Joseph Reekers is convicted of the 2001 murder of Aucklander Marie Jamieson. Police traced him through a familial search of the DNA databank, which discovered the profile of semen from her clothing was a partial match with that of his sister. Reekers was ordered to give a sample when he was arrested for shoplifting in 2008.
Read the full story about the extraordinary crime-solving power of DNA and the debate over whether its use is breaching our privacy and human rights in the latest issue of the Listener, on newsstands now. Is our legislation keeping up with the rapid advances in the field?
This article was first published in the June 30, 2018 issue of the New Zealand Listener.
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