Elizabeth Woolcock is believed to be the only female ever executed in South Australia.
On December 30, 1873, she was hanged at Adelaide Gaol — at the age of just 25 — after being convicted of poisoning her abusive husband with mercury at their Moonta cottage.
Her trial was a sensation and even at the time, strong doubts were expressed about the soundness of the verdict.
"The trial she had was, I consider, very biased. Even though there was not a lot of evidence presented against her, the jury seemed to think that she was guilty," said author and researcher Allan Peters.
"The evidence to my mind certainly didn't appear that way."
Woolcock's harrowing story has haunted the Peters family for four decades, and has spread across generations.
Mr Peters, 86, has fought to clear Woolcock's name, and has now passed on that project — and his passion — to his daughter Leeza.
"Elizabeth Woolcock basically feels part of our family."
The family obsession has been motivated by what they consider to have been an unfair trial, as well as Woolcock's personal story of hardship and horrific abuse.
Born Elizabeth Oliver in Burra in 1848, she and her family left for the Ballarat gold fields after their home was washed away in a flood.
Ms Peters said it was while in Victoria that she was abandoned by her mother, and "at the age of seven, she was raped by a miner".
After learning of her mother's whereabouts, she moved to Moonta in South Australia, where she married Thomas Woolcock, who was abusive towards her, Ms Peters said.
When he fell ill, his wife and doctors treated him, including with morphine, and it was not until rumours circulated after his death that Elizabeth Woolcock fell under suspicion.
History suggests that after she was arrested, she was assigned an inexperienced lawyer.
Even though it was never proven that her husband had died of mercury poisoning, or that Woolcock had administered it, she was found guilty of murder.
"A chemist who was following the case wrote to the governor at the time [providing] 26 reasons why she shouldn't be executed," Ms Peters said.
"This story is an unusual one. Women were treated differently back then. I am so glad that there has been some change now.
The Peters family has twice applied unsuccessfully for a posthumous pardon.
The Governor of South Australia has the power to grant such a request, but legal expert Dr Bob Moles said that if the evidence was sufficiently compelling it could be taken to the Court of Appeal.
"If the legal system has done wrong by somebody for wrongly convicting them then the passage of time should not change that and everyone should have the chance to have their case reviewed," he said.
"There would be a good case to put to have the conviction reviewed and I think there would be a clear possibility that an appeal court could well decide that conviction is unsafe and set it aside."
While the cost of any such exercise might prove prohibitive, Ms Peters will continue to do her bit to see Woolcock exonerated.
"If I can help with that in any way, that's what I believe I'm here for."
