Chris Pearman heads South Australia's rise to forensic science world renown from 1980s with DNA testing to the fore
Chris Pearman, who started working as a botanist with the South Australian police technical services branch and later became director of Forensic Science SA, saw the vale of DNA testing when paedophile Dieter Pfennig was convicted, after 30 years, for the 1983 murder of 11-year-old Louise Bell (inset left). Pfennig also killed Michael Black (inset right) in 1989.
Chris Pearman was a continuum in the growth of South Australia’s world-renowned crime forensic science and the crucial breakthrough use of DNA (deoxyribonucleic acid) that confirmed Pearman’s early find in solving the Louise Bell murder case.
With his father John a geologist, Pearman had decided on becoming a marine biologist from family trips to the Flinders Ranges and summer holidays at Port Elliot. After attending St Peter’s College, he studied botany and zoology, including genetics, at Adelaide University, graduating in 1978.
His plan to study marine biology in Townsville was altered by his former Adelaide University lecturer, professor Bryan Womersley, telling him about a job as botanist with the South Australian police’s technical services branch. For the next five years. Pearman’s duties at the branch involved analysing botanical evidence in criminal cases mainly related to outdoor cannabis crops being grown by Italian organised crime syndicates.
In the early 1980s, after forensic evidence presented by the police technical service branch in the murder trial of Edward Charles Splatt was heavily criticised in a royal commission that acquitted Splatt, an independent state forensic science centre – the forerunner to Forensic Science SA – was created in 1985. Pearman and several colleagues left the police force and joined the unit. Pearman slowly became more involved in other biological evidence recovery and analysis techniques using ABO blood groupings, serum proteins and enzymes to identify and link suspects to crimes. This piqued his interest in emerging DNA technologies.
In 1998, Pearman became biology unit manager and Forensic Science SA to the forefront of forensic DNA analysis nationally. He became Forensic Science SA director in 2013 after incumbent professor Ross Vining died in a Queensland plane crash.
The Louise Bell case was the most challenging of Pearman’s career. Bell, aged 11, was abducted from his Adelaide southern suburbs Hackham West home in 1983 and her sleeveless cotton pyjama top was left neatly folded on the front lawn of a house near the abduction site. With help from professor Womersley, Pearman found botanical evidence on the top: a rare algae – wittrockellia salina – from the Onkaparinga River in the southern suburbs.
The algae was the first big lead in the case but it was microscopic particles of saliva or blood containing the DNA of paedophile Dieter Pfennig, clinging to the fibres of the pyjama top, that would eventually – with advances in DNA testing technology – ensure his conviction for the Louise Bell murder 30 years later in 2016. Pfennig already had been convicted of abducting and raping another child, who survived, in 1989 and, months later, abducting and murdering Michael Black, 10. He was sentenced to a non-parole term of 60 years.
