The High Court of Australia has ordered a retrial of deregistered psychiatrist Jean Eric Gassy, who was convicted in 2004 for the murder of former SA mental health chief Dr Margaret Tobin.

The Court held that a direction to the SA jury by the trial judge Justice Ann Vanstone was not sufficiently balanced, and resulted in a miscarriage of justice requiring a new trial.

Tobin, who had worked as a psychiatrist and mental health administrator in Victoria, NSW and SA, was shot four times on 14 October 2002, as she left a lift, returning from lunch to her office in central Adelaide.

Gassy allegedly shot Tobin due to resentment and anger from her part in initiating a process that led to his deregistration as both a medical practitioner and psychiatrist when Tobin was working in Sydney.

A judgement issued this morning by the High Court said, in part:

The facts as alleged by the prosecution case at trial included the following. Six months before the murder, Mr Gassy, an experienced pistol shooter, booked into a Brisbane motel under a false name and acted suspiciously at a Royal Australian College of Psychiatrists’ conference where Dr Tobin was to speak. Just before the killing, he booked into an Adelaide motel under a false name. On each trip hire cars were booked in false names. Gunshot residue of the same brand of ammunition used to kill Dr Tobin was found in the hire car in which Mr Gassy drove to Adelaide. He owned pistols and ammunition of the kind used to kill Dr Tobin.

In Brisbane, a man matching Mr Gassy’s description bought a part for a Glock 26 pistol at a gunshop, and gave the name Gassy or Gass, his firearms licence number and his sister’s mobile phone number as a contact number. A receipt for the purchase was found at his flat. Other receipts were found … after a man was seen putting a plastic bag in a service station bin.

After lengthy deliberations, the South Australian criminal trial jury reported that it was deadlocked and sought further guidance from the judge. The guidance the judge gave about the prosecution’s largely circumstantial case was found to be not sufficiently balanced by a 3-2 decision of the High Court.

The High Court decision is sending shockwaves through the SA police and legal community, as well as the medical profession and health administrators across the country.

It is expected that Gassy will apply for bail. It is also expected this will be strongly opposed by the SA DPP.

Gassy, who appeared for himself during the SA trial, refused the offer of senior counsel to appear pro bono on his behalf before the High Court, instead arguing his own case.

The SA police and prosecution now face a long arduous task of re-assembling evidence and witnesses, while the families of Tobin and Gassy also face another long and trying legal process.

The full judgement is available here.

Melissa Sweet is the author of Inside Madness (Pan Macmillan 2006), which covered the story of Dr Tobin, her involvement in mental health reform, and her murder.