The lawyer for double murderer Scott Watson has slammed the police tactics used to identify his client as the killer of Blenheim friends Ben Smart and Olivia Hope in 1998.
Nick Chisnall, KC, told the Court of Appeal it was clear that police exerted significant "interrogative and moral pressure" to get the key witness — water-taxi driver Guy Wallace — to change his story.
Mr Smart, 21, and Ms Hope, 17, have not been seen since getting out of the water taxi and on to a yacht moored in Endeavour Inlet early on New Year’s Day 1998. Their bodies and possessions have never been found.
Police showing Mr Wallace a photo of Watson in early January — which neither Watson’s trial lawyers nor the jury were allegedly told about — only reinforced why Mr Wallace’s identification was inadmissible, he said.
"Police concertedly and repeatedly used suggestive practices ... to secure Mr Wallace’s identification of Watson," he told the court yesterday.
"The evidence unequivocally proves that police showed a single photo of Mr Watson to Mr Wallace in the investigation in January 1998. And given that a single photo was shown to other key witnesses, this was plainly an investigative strategy, rather than a misstep by an overzealous officer failing to follow instructions."
Then, three and a-half months later, police showed Mr Wallace another photo montage, known as montage B.
Mr Chisnall said the photo police used of Watson half-blinking made him stand out and was shown to Mr Wallace after there had been "media saturation" of Watson’s image.
Yet he suggested that without Mr Wallace identifying Watson in montage B, there was no identification at all and Mr Wallace’s evidence would have lost its "vigour".
Mr Chisnall told the court Watson’s team were asking the court to allow the appeal, but in doing so not to order a retrial.
Earlier in the day, Watson’s other lawyer, Kerry Cook, questioned DNA expert Prof Mitchell Holland from the University of Pennsylvania, who gave evidence by audiovisual link.
The defence claims the DNA evidence used to convict Watson was overstated at trial. They argue the absence of a New Zealand DNA database means the methods used at trial to compare Mr Hope’s DNA, taken from hairs on a blanket found on Watson’s boat Blade, with one from an overseas database, cannot be relied upon.
By Catherine Hutton
