The police and ESR have used DNA to solve some of New Zealand’s most infamous crimes. The following is an extract from A Brief History of Forensic DNA 1990-2010, by ESR.
Teresa Cormack Case
In 1987, six-year-old Teresa Cormack went missing. Eight days later her body was discovered. Hairs found on her body were examined and stored. Swabs were sent to Britain for testing but contained insufficient material to provide a proﬁle.
In the 1990s the remaining swabs were retested – again there was no result. Then in 2001, following signiﬁcant developments in DNA technology, the remaining forensic evidence was examined. This time a proﬁle was extracted from a very small amount of semen saved on a microscope slide.
A massive screening exercise began to identify a potential match. One was found – Jules Mikus. To conﬁrm the match, the hairs stored for 15 years were ﬂown to the United States and exposed to mitochondrial DNA extraction (the DNA located in structures within cells that convert the energy from food). The resultant DNA proﬁle matched the proﬁle obtained from Mikus’ blood. Further blood samples conﬁrmed the match.
Fifteen years after the murder Jules Mikus was found guilty of the abduction, sexual violation and murder of Teresa Cormack.
Maureen McKinnel case
Following the success of the Cormack case, the officer-in-charge of a 16-year-old homicide case in Arrowtown asked that samples be retested using new DNA testing methods.
The victim’s reference proﬁle was determined from the remains of a blood sample, and this was compared with DNA obtained from her nail clippings. The clippings resulted in DNA proﬁles of two males.
The Police began the process of reviewing their suspects. One of the proﬁles belonged to a legitimate male contact. The following year, Jarrod Mangels provided a voluntary blood sample.
The database recorded a proﬁle match to the McKinnel case. Sixteen years after the murder, Mangels was arrested and charged. In February 2004, he pleaded guilty to the crime, apologising in the courtroom. He was sentenced to life.
Lois Dear case
In July 2006, the body of 66-year-old teacher Lois Dear was discovered in her Tokoroa classroom at Strathmore Primary school. There were no ﬁngerprints, nor any blood found at the scene; however, there was a hair and a shoeprint. Ten years earlier it wouldn’t have been possible to collect DNA from a single strand of hair. However, new technologies led to the identiﬁcation of the hair as belonging to 23-year-old Whetu Te Hiko.
In addition, shoeprints invisible to the naked eye were discovered at the scene of the crime, leading from the classroom to a bathroom. ESR scientists lifted the prints using an electrostatic dust-lifting kit.
The soles of the shoes were identiﬁed as a brand sold at the Warehouse in Tokoroa. Police discovered only three pairs had been sold, only one in the size that Te Hiko wore. Police then trawled through store security tapes for that particular occasion and found video of Te Hiko purchasing those shoes.
Te Hiko pleaded guilty to the murder and in May 2007 was sentenced to life imprisonment with a minimum of 18 years non-parole.