Ross was arrested almost two weeks after the murder. He was accused of luring Alma into his wine bar, plying her with alcohol, then raping and strangling her. The girl was abducted, raped and strangled. Her body was dumped in a lane called Gun Alley. Her body was found on New Year’s Eve.
Ross, 28, the licensee of a wine bar nearby, was charged with the killing.
Strands of hair found on a blanket at his home were tested by a government chemist and were said to have matched samples of Alma’s long, dark auburn locks. It was the first time a forensic comparison of hair had been used in an Australian court — evidence that 75 years later was proved false.
The prosecution produced three witnesses — a sex worker, a prisoner previously convicted of perjury and a fortune teller to attest to Ross’ guilt. Ross was found guilty in the Supreme Court. He was accused, tried, convicted and executed in just four months. He hanged, in part, because of bungled forensic evidence used in court for the first time.
Ross' barrister, Thomas Brennan, was convinced of Ross’ innocence and campaigned to have the case reviewed but public interest waned. Brennan remained supportive of Ross and certain of his innocence, but had exhausted all avenues in his attempt to save Ross from execution. Brennan became consumed with his failure to save the life of Colin Campbell Ross, eventually writing a book, 'The Gun Alley Tragedy', in which he attempted to establish that Ross had been hanged for a crime he did not commit. Although Brennan attracted supporters, it was not enough to persuade the Victorian government to have the case re-examined.
In 1993, Kevin Morgan, a former school-teacher, became interested in Ross' case, and began to research the events surrounding the murder of Alma Tirtschke and Ross's execution. He was fascinated and began to investigate the case. Two years later, he quit his job as a librarian and began full-time work on investigating the case.
Morgan's painstaking research raised serious doubts about the Ross conviction and located the strands of hair tested in the original case.He found Alma was never at the wine bar, that Ross was there when Alma was snatched, and that a man known to Alma and her sister, and who had made them uncomfortable, was the likely killer.
Two years after he began researching the case, Morgan found a file in the Office of Public Prosecutions containing the original hair samples, which had been thought lost. He began a long administrative struggle for the right to submit the hair samples for DNA testing, finally achieving his aim in 1998. Two independent scientific authorities - the Victorian Institute of Forensic Medicine and the forensics division of the Australian Federal Police - found that the two lots of hair did not come from the same person, thereby disproving with certainty the most damning piece of evidence presented at Colin Ross's trial.
This included a modern DNA examination of the hair samples compared in the original case, which found those discovered in Ross’ house did not match Alma’s.
This sparked an inquiry by three Supreme Court judges, who found there had been a miscarriage of justice in the case.
In 2008, Governor David de Kretser signed Victoria’s first posthumous pardon for Ross 86 years after he went to the gallows. In October 2010, Ross's remains were exhumed, identified and handed to his family for a proper burial.
Almost a century on, the scars on both families remain.
On the subject of capital punishment, let this case be an example that there is no such thing as a perfect criminal justice system.
Before Ross' execution, in his farewell letter to his family Ross wrote; "The day is coming when my innocence will be proved."
Ross composed himself with dignity for his quiet but resolute statement from the scaffold. "I am now face to face with my Maker, and I swear by Almighty God that I am an innocent man. I never saw the child. I never committed the crime, and I don't know who did. I never confessed to anyone. I ask God to forgive those who have sworn my life away, and I pray God to have mercy on my poor darling mother, and my family."
Ross was hanged in a gruesome and shocking manner. Authorities had decided to experiment with a four-stranded rope rather than the usual three-stranded European hemp. The four-stranded rope did not run freely through the noose and Ross did not die immediately because his spinal cord was fractured, not severed. Although his windpipe was torn and obstructed by his destroyed larynx, the condemned man continued with rasping breaths and convulsed on the rope. Three times Ross bent his knees and flexed his arms before succumbing, slowly strangled to death by asphyxiation. A prison report later ruled that such a rope must never be used again.