It was a grisly find, even for the most seasoned detectives.
Passers-by called it in. Firefighters arrived soon after.
From a distance, it was hard to make out what was burning on the verge of a rural road near Gympie, on Queensland’s Sunshine Coast.
As they got closer, it became horrifyingly clear: a human torso was on fire.
Bodies of evidence
A qualified forensic anthropologist, Senior Sergeant Donna MacGregor was lecturing at university and working part-time with the Queensland Police Service (QPS) in 2013 when she was asked to help identify the roadside remains.
Known as the “bone lady”, she has been investigating ways the dead can tell their tales for almost three decades, helping solve some of the state’s most high-profile crimes.
Almost three decades after joining the police force, Donna MacGregor remains passionate about her work. (ABC News: Michael Lloyd)
Senior Sergeant MacGregor moved from academia to the QPS about 25 years ago. An army reservist, she also travels to battlefields to identify the remains of Diggers for the Australian Defence Force.
She is QPS’s only forensic anthropologist and the officer in charge of the major crime forensic unit, which takes its expertise to the most serious crime scenes.
Like the grimly puzzling case of the burning torso.
With the head and hands missing, there were no fingerprints to match on a database and no dental records to search.
“In this day and age, everyone thinks DNA will solve everything — and it does in a lot of cases,” Senior Sergeant MacGregor said.
“In this case, the body did not have a DNA profile on record … [and] because of what had happened to the body, there weren’t a lot of those traditional areas you would use for identification.”
Teeth and hair would have made it easier to determine that the torso belonged to 66-year-old George Gerbic, from the Sunshine Coast.
But without these, it took 12 months to establish his identity.
Lindy Williams (right) has been sentenced to life in prison for the murder of her partner George Gerbic. (Supplied)
Senior Sergeant MacGregor got permission from the state coroner to remove part of a rib bone from the then-unidentified torso.
Due to the way bone changes over time, the part of the human rib that connects to the sternum is one of the most accurate ways to determine age.
Insects and drugs
Beetles were then used to remove the tissue from the bone.
“There’re other ways to do it, but you could potentially damage the bone,” Senior Sergeant MacGregor said.
Testing also found traces of a prescription drug.
“They went right through the Sunshine Coast area where the body was found and looked at all the prescriptions for people who were using those particular drugs,” Senior Sergeant MacGregor recalled.
Lindy Williams walks through a house with police during the investigation into George Gerbic’s death. (Supplied: Supreme Court of Queensland)
“Once we had a biological profile … they could then go looking for a male person of a certain age who was on this medication and it helped to narrow down that potential search list.”
In 2018, Lindy Williams, Mr Gerbic’s partner, was sentenced to life behind bars for his murder.
Donna MacGregor says Lindy Williams (left) was arrested a week after George Gerbic’s remains were identified. (Facebook)
The Queensland Supreme Court heard during her trial that, after Williams dismembered the body, she orchestrated a sophisticated cover-up for 10 months, telling friends and family Mr Gerbic was still alive.
“Once we had identified the victim, within a week the offender was arrested and that was after nearly 12 months it took to identify the body,” Senior Sergeant MacGregor said.
Reading skeletonsÂ
The role of forensic anthropology is to learn the ancestry, sex, age and stature of a person from their remains. It is a key element of some murder investigations.
“What’s their genetic origin? Where did they come from? And how might that fit back into a story, or a version, if it’s in the criminal space?” Senior Sergeant MacGregor said.
Donna MacGregor (left) leads the major crime forensic unit. (Supplied: Queensland Police Service)
Injuries to a skeleton also tell a story.
“We call them defects,” she said.
“Can we interpret (a defect) in terms of being the cause of death? Or is it just a congenital abnormality in the skeleton?”
Senior Sergeant MacGregor was a post-graduate student at the University of Queensland when her supervisor introduced her to the criminal cases he was working on with police.
Biomedical sciences students at QUT learn from Donna MacGregor. (ABC News: Josh Bavas)
“I used to talk with him about different things and that’s when I got my first insight into forensic policing,” she said.
“So down the track I made the decision that I was going to give it a go.”
She started in general duties in Brisbane, looking at major crime scenes, from rapes to fire investigations.
Finding Daniel Morcombe
In 2010, Senior Sergeant MacGregor took leave without pay from the police service and returned to academia at Queensland University of Technology.
She was teaching anatomy and compiling a virtual database with research students when QPS asked her to help with a complicated crime scene in the Glass House Mountains, where a large search was getting under way.
It would eventually recover the remains of 13-year-old Daniel Morcombe more than half a decade after he was abducted from a Sunshine Coast bus top and murdered by Brett Peter Cowan.
The search area for murdered schoolboy Daniel Morcombe was daunting, recalls Donna MacGregor. (Supplied)
Daniel’s bones and clothing were found scattered in sand and mud near a macadamia farm at Beerwah in 2011.
“That was a long, protracted [crime] scene,” Senior Sergeant MacGregor recalled, on a scale not seen in Queensland.
“Given the vastness of the area, I never thought it would be a case we would ever solve, in all honesty,” she said.
Two significant flooding events across the area also added to the complexity of the search, with river experts brought in for advice.
An area where items were found in the search for Daniel Morcombe. (Supplied: AAP/Queensland Courts)
“I still think it was one of the biggest crime scenes ever, but we would never have been able to have the success to find him without the investigators who put strategies in place to find that location,” Senior Sergeant MacGregor said.
“If you think about all the forestry areas up there, it is a needle in a haystack.”
The investigation included crime-scene officers, detectives, forensic investigators and volunteer State Emergency Services (SES) searchers.
“So many SES people gave up their time,” Senior Sergeant MacGregor said.
Zoologists also provided expertise.
This shoe found in the Sunshine Coast hinterland belonged to Daniel Morcombe. (Supplied: AAP/Queensland Courts)
“They could talk about animal behaviour and we had the botanists come in to interpret all the trees — a lot of different specialties went into it,” she said.
“We were able to find this young boy and give him back to his family and that is very powerful.”
Providing closure to families is a main goal of all investigations, but during searches like that for Daniel, forensic officers focus on scientific proof.
Brett Peter Cowan is serving a life sentence for the murder of Daniel Morcombe. (Supplied: Queensland Supreme Court)
“When we’re doing these recoveries, we can’t put names to them,” she explained.
“We believed it was Daniel but we still had to go through the process to prove that scientifically.”
Staying objective amid grief
Not dealing directly with grieving families helps Senior Sergeant MacGregor’s team remain impartial, even when dealing with grisly scenes.
“It allows us to maintain our objectivity without any biases or anyone trying to influence the process we go through, our scientific method to try and prove what we can prove,” she said.
Donna MacGregor says her team, which includes scientific officers, do amazing work every day. (ABC News: Michael Lloyd)
“We know this is a person and this person was loved but at this point in time our job is to process this scene and help find out what happened to them, so we can then give them to their family.
“I think you end up compartmentalising.”
Fallen soldiers
These days, Senior Sergeant MacGregor spends less time at crime scenes and more time in the lab mentoring other officers and providing expert advice.
In her spare time, she is part of the Australian Defence Force’s unrecovered war casualties team, which accounts for missing soldiers from past conflicts.
“Every set of human remains, every skeleton I look at is unique and every job teaches you something … it’s an interesting process to go through to essentially read the skeleton,” she said.
“I know that sounds so cliche but you are going through it, documenting and recording what’s there to see what it can tell you.
‘Body farm’ helps train next generation of first responders
“In Europe, when we’re looking at WWI remains, the position of bodies can tell us whether they’re buried by the enemy or whether they’re buried in haste or whether it was a battlefield burial.”
Almost three decades after joining the police, Senior Sergeant MacGregor is as passionate about her work as she was early in her career, but is quick to add that solving major crimes is a group effort.
“This is a team of people that achieve these results,” Senior Sergeant MacGregor said.
“It’s like a big puzzle and everyone’s part of that puzzle.
“There’s so much that the skeleton can tell you, and it is just amazing.”