Forensic evidence has helped solve crimes since the days of Roman Emperor Julius Caesar’s assassination, when an autopsy determined only one of the 23 stab wounds was fatal. With technology more sophisticated than ever before, today, scientists can use a single hair follicle to link a criminal to a crime scene. But should we always rely on DNA evidence to prove guilt or innocence?


On Sunday 1 March 1998, Kathleen Marshall’s decomposing body was found in her Australian veterinary clinic by two colleagues.
She had more than 50 stab wounds to her face, head, arms, chest and abdomen.
Kathleen, dubbed ‘Catwoman’ by the media, was president of the Cat Protection Society of Queensland.
Andrew Fitzherbert was named as prime suspect, due to ‘five drops of blood’ at the scene.


He steadfastly maintained his innocence, declaring he had ‘never met’ Dr Marshall. Fitzherbert didn’t have any direct link with Kathleen, but he was friends with Virginia Houston – a rival to Kathleen at the Cat Protection Society.

Fitzherbert lacked an alibi for the estimated time of death, which he maintained was miscalculated. There was uncertainty over Kathleen’s time of death, but the trial was conducted on the basis that she died either on the night of Thursday 26 February 1998, or early on Friday 27 February 1998 before 3pm.

This estimate was based on the evidence of entomologist Russell Luke, who arrived at this prediction from his analysis of the maggots found on Kathleen Marshall’s body when she was discovered at around 2.30pm on 1 March.

In contrast, the evidence from six witnesses, all of whom knew Kathleen Marshall well, was that Marshall was alive and well on Friday 27 February as she went about her normal daily routine.

She was sighted on several occasions by these witnesses both in the morning of Friday 27 February as well as in the afternoon.

The last reliable sighting was by a neighbour at 4.45 pm on that afternoon.

If the evidence of these witnesses is accepted, it seems that Kathleen Marshall was killed sometime between 4.45 pm and about 7 pm on Friday 27 February 1998.

When you add to this that a single scream was heard at 6pm by a total of three people who had been standing just 50 metres from Marshall’s house you have strong evidence of her time of death.

Andrew Fitzherbert had a very good alibi for this latter time period of Friday afternoon and evening, since he was with friends at a meditation session and seance.

He did not have a good alibi for the earlier time period and, in 1999, he became the first Australian man to be convicted of murder based solely on DNA evidence.

No murder weapon was ever found, there were no witnesses, and Fitzherbert had no motive for the brutal attack.

Fitzherbert mounted an appeal claiming the DNA evidence had been faked, however this was rejected by the Court of Appeal.

He was released on parole after 14 years behind bars and it was reported that he spent his 66th birthday having a low-key meal at a restaurant.

Following his release in 2014, Fitzherbert’s lawyer Joe Crowley commented, ‘He’s remarkably sanguine about it. There’s no burning anger.’

To this day, Fitzherbert is still seeking to clear his name.