Digging deep to find the culprit

By / 27th of May, 2014

GETTING the dirt on someone takes on a whole new meaning when Robert Fitzpatrick is involved. His approach has helped convict criminals in Australia and terrorists overseas.

A specialist in the emerging field of soil forensics, Professor Fitzpatrick uses information gained from even the most minute of soil samples to reveal where people and things have been – which is usually where people say they haven’t.

He has run the Adelaide-based Centre for Australian Forensic Soil Science (CAFSS) for over a decade and recently developed a comprehensive manual to help others around the world follow in his footsteps.

CAFSS is the only dedicated soil forensics centre in the world and has assisted with 130 cases in Australia and overseas, 30 of which have gone to court. Around 15 per cent of these are anti-terrorism cases, involving agencies such as Interpol, the FBI, DSTO and the Australian Federal Police.

“We get sent shoes and bits of clothing from as far afield as Africa or the Middle East and are asked to find anything that can link them to a specific place.”      Prof Robert Fitzpatrick

Doing that involves a mix of skills, including pedology (how soils form) and mineralogy (the analysis of tiny soil particles). Prof Fitzpatrick studied both in his native South Africa before moving to Australia 34 years ago.

His move into forensics happened largely by accident, however.

In 2000 he was doing complex but generally more conventional soil science for the CSIRO when he and colleagues were asked to help South Australian police with a frustrating double murder case.

They were able to link soil found on a shovel in a suspect’s car to a specific quarry in the Adelaide Hills, and the bodies were found less than 15 metres from where they predicted they would be.

Not surprisingly, the idea of getting soil to talk caught on, and Prof Fitzpatrick found himself on a steep learning curve as he added to his own skills and created the model for a modern forensic soil research capability.

Around 80 per cent of the work is core science, he says. The remainder (which is the focus of his Guideline manual) is understanding the chain of custody and learning how to write reports and handle the legal system.

“Once you are part of that system and proving to be of use, then clever lawyers quickly start learning how to question what you do,” he said. “That has been the really challenging part for me to learn.”

Prof Fitzpatrick and his team have since published several papers and encyclopaedia chapters, including case studies based on their completed investigations.

The basic concept of soil forensics is not new. Studying soil is believed to have helped find who stole coins from a Prussian train in the 1850s and police used soil information extensively during the 1990s.

However, the police capability could not keep pace with advances in technology, meaning that, according to Prof Fitzpatrick, “critical forensic evidence was often missed or ignored completely”.  That changed with the success of 2000, and the establishment of CAFSS three years later.

The work can often be painstaking. In one complex murder case Prof Fitzpatrick and his team spent two years successfully linking minute brick particles in a murder victim’s bra and hair to a collection of old brick pavers in the front yard of the victim’s home – even to one specific type of brick.

And things keep changing, which is probably not surprising for a discipline rooted in both science and the law.

Most notably, courts are now testing whether forensic soil scientists can and should provide insights into the transference of soil – moving beyond stating what soil was found where to actually suggest how it might have got there.

“That’s a whole new ball game,” Professor Fitzpatrick said.

CAFSS is administered by CSIRO Land and Water at the Waite Precinct in Adelaide. Its partners include Forensic Science South Australia, the Chemistry Centre Western Australia, the Australian Federal Police, the National Institute of Forensic Science, South Australia’s three universities (the University of Adelaide, Flinders University and the University of South Australia) and the University of Canberra and the University of Tasmania).

Guidelines for Conducting Criminal and Environmental Soil Forensic Investigations (.PDF)

Key contacts

Prof. Rob Fitzpatrick Director Centre for Australian Forensic Soil Science
61 8 8303 8511 Rob.Fitzpatrick@csiro.au
  • Soils make good evidence. They are highly individualistic, are easily described by colour and via a range of analytical methods, and transfer easily. And while they are often virtually invisible to the naked eye, they are easily located using hand lenses or light microscopes.
  • Five cases in Australia have been solved without forensic work actually being carried out. Detectives have simply told suspects or their legal teams that soil samples have been or will be collected for investigation and comparison by forensic soil scientists.
  • As well as working on a range of complex murder cases, CAFSS helped solve the illegal clearance and theft of tree ferns worth $11 million from national parks in Victoria.
  • Professor Fitzpatrick doesn’t read crime novels, but he did once meet Ian Rankin (creator of the famous Scottish detective John Rebus) at a conference in Edinburgh.