David Charles Benbow denies murdering Michael McGrath and is standing trial at the High Court in Christchurch. Photo / Kai Schwoerer, Stuff, Pool
Detectives snuck a secret tracking device beneath a murder suspect’s car after making a “tactical media release” about a global search expert’s help, hoping he would lead them to a dumped body, a court heard today.
Ex-prison officer David Benbow is standing trial for the alleged murder of Christchurch builder Michael McGrath who disappeared from his home in the city suburb of Halswell on May 22, 2017.
His body has never been found – and nor has a murder weapon - despite vast Canterbury-wide police searches that included officers spending two months scouring an enormous landfill site.
Benbow, 54, was arrested more than two years later and has always professed his innocence.
Today, at the High Court in Christchurch, a seven-week murder trial finally began before a jury of seven men and five women.
Benbow’s defence team warned the jury of “investigative bias” and “tunnel vision” from police early in its probe.
In an opening address, Marc Corlett KC said that “within hours” of McGrath’s disappearance, Benbow’s ex-partner, who was in a new relationship with McGrath, had pointed the finger of blame at Benbow “and the police duly obliged”.
But despite teams of police spending thousands of hours investigating “trying to find any evidence they could to fit their theory”, they could not find any, Corlett said.
Issues of a particular witness and CCTV evidence that the Crown will say puts McGrath at Benbow’s house on the morning he was allegedly killed was also flagged up by the defence, with Corlett warning the jury not to “swallow whole” the Crown story.
The Crown gave an opening address that outlined its case against Benbow, alleging that he murdered his old schoolmate McGrath just weeks after finding out he was seeing his ex-partner and telling a counsellor he wanted to “annihilate” him.
After spending days plotting and preparing, Benbow had the motive, means and opportunity to kill McGrath, Crown prosecutor Claire Boshier told the court.
Benbow went to McGrath’s house on Sunday, May 21, 2017, and asked if he’d help him shift some heavy railway sleepers the following morning at his semi-rural lifestyle block.
In an hour or so window, it’s the Crown case that Benbow used his .22 semi-automatic rifle, with suppressor and sub-sonic ammunition, to murder McGrath and then dispose of his body.
While the Crown accepts there is no body, no murder weapon, and little forensic evidence in the case, it says there is a strong circumstantial case consisting of many threads that, when taken together, show Benbow is guilty of McGrath’s murder beyond reasonable doubt.
As the police investigation into McGrath’s disappearance progressed, Benbow became a person of interest and, in July 2018, officers put a covert tracking device on his Toyota Camry.
It came after releasing a “tactical” media statement which said police were working with an international search expert and had identified geographical areas of interest in the greater Christchurch area that specialist search teams would focus on.
The court heard that the tracking device’s logged daily summaries showed a consistent pattern of movements for Benbow around Halswell and its surrounds, visiting friends, family, the supermarket and petrol station.
Other trips outside of town were backed up by intercepted voice calls.
But two trips - on August 6 and 7, 2017, just after the planned police media statement - were different, the Crown alleges.
They say that at about 7.50pm on August 6, Benbow drove to a rural address in Motukarara and stopped for more than two minutes.
On the following morning, he allegedly drove to the same area and stopped at two other spots.
They were the only times he went to that area in five months of surveillance, the Crown claims.
Boshier posited whether Benbow was checking the area to see if police had gone there searching for the body.
Police searched sections of the Halswell River and surrounding wetlands but found nothing, with Boshier likening it to finding a “needle in a haystack”.
The court heard how Benbow had allegedly been devastated after learning that Joanna Green, his partner of 17 years, had taken their two children and left earlier in 2017.
And when one of his children had told him they had seen “Mummy and Mike kissing” on April 30, his “world changed”.
Two days later, after calling in sick at Christchurch Men’s Prison, Benbow visited a counsellor to speak about his break-up, saying he was lost and lonely.
He said his health was deteriorating and couldn’t sleep or eat.
Benbow, the Crown says, also spoke about the assets he’d had with Green, including three rental properties, and that he felt “shafted” - something the counsellor had underlined in her notes.
He also allegedly told her that one of his mates was seeing Green now and that he wanted to “annihilate” him.
Over the summer of 2016/17, Benbow had hired his mate McGrath – a carpenter who did cash jobs for friends and through word-of-mouth - to build a large new deck at their Candys Rd family home.
It was a big job that the meticulous and exacting builder took months to complete.
Later, Benbow would say to friends that he suspected something was going on between McGrath and Green while he was away in Wellington training to become a Corrections officer.
The Crown alleges after finding out about the relationship, he planned to kill McGrath.
It is alleged that Benbow turned off the CCTV at his Candys Rd property – something he was obsessed with, Boshier says – so that his comings and goings in the weeks he was “finalising his plan” were not recorded.
Benbow would later tell police that McGrath never showed up.
But the Crown says CCTV cameras – and a witness – show that McGrath did keep his word that day and showed up around 9am.
Benbow was late for a 10am counselling appointment in Riccarton, the Crown alleges.
“Exactly what he did in that hour when he murdered Mr McGrath is not known,” Boshier told the court today.
What is known, the Crown says, is that Benbow’s legally purchased Marlin 795 .22 semi-automatic rifle which he said was secured in his roof space is missing.
The use of such a low-power rifle, along with suppressor and sub-sonic ammunition would not make much of a noise, Boshier said, rather it would be “more akin to a click”.
And .22 calibre bullets do not usually exit a body, the prosecutor said, nor would there be a large dispersal of blood or bone fragments at the scene.
The Crown alleges that on his way back from his counselling session, Benbow bought a packet of grass seed – along with more petrol.
And when police examined Candys Rd, parts of the lawn around the deck area had been dug out and fresh grass seed sown despite it being nearly winter, the Crown says.
It was a place he had “selected carefully” and had time to prepare, Boshier told the jury.
Massive searches for McGrath around waterways around Halswell were conducted by police – along with the Kate Valley landfill site after it was established Benbow went to the city council-run Parkhouse Rd refuse centre the day after it’s alleged he killed McGrath – but his body has never been found.
McGrath’s bank accounts have not been touched since his disappearance.
Benbow hardly used his cell phone on May 21, 22, and 23, 2017, the Crown says.
But Boshier highlighted a couple of “interesting” internet searches, including on May 21 “what are the organs of the human body” and, later, a search for a map of the Lincoln area.
This afternoon, the court heard from the trial’s first witness: Simon McGrath, brother of the missing, suspected murdered man, who described Michael as a gifted, hard-working builder, all-around good guy, and dependable “creature of habit”.
On Tuesday, May 23, when Michael didn’t show up for the usual dinner at their mother’s house in Halswell, he thought it was unusual.
Within minutes, Green had phoned his mother, saying she thought something had happened to McGrath and that “Dave had done something”.
They had to break into McGrath’s locked house and when he was not found inside, they phoned police, who suggested they go to the station to make a report.
On the way, Green phoned Benbow, Simon McGrath said today, and she asked what he had done with Michael.
He recalls her saying she would phone the police, after asking where Benbow was.
As soon as she ended the call, she phoned someone else to check out his story, Simon McGrath said.
“When she hung up, she said, ‘He’s a lying bastard’,” he told the court.
The trial, before Justice Jonathan Eaton, continues tomorrow.
The 17-year-old was last seen in Albany on Friday.