Fingerprints taken from accused Claremont serial killer Bradley Robert Edwards in 1990 were part of the breakthrough police used to allegedly solve a 1988 Huntingdale prowler case, and in doing so, allegedly catch WA's most wanted killer.
Mr Edwards, in 1990, was working at Hollywood Hospital as a Telstra contractor when he attempted to drag a young woman from her desk into a toilet block.
The social worker was attacked by Mr Edwards from behind, with the then 20-year-old stuffing a piece of fabric into her mouth.
The woman kicked her attacker and broke free, with security guards holding Mr Edwards until police arrived.
He apologised and pleaded guilty to common assault.
Mr Edwards' fingerprints were entered into a national database soon after his arrest in 1990.
More than 20 years later, cold case detectives re-examining a kimono left behind at an attempted sex attack in Huntingdale in 1988 discovered that the garment allegedly contained the same male DNA profile found on Ciara Glennon and the Karrakatta cemetery rape victim.
Around the same time the 1988 Huntingdale attack occurred, a 'prowler' had been lurking around the south-eastern suburb, stealing women's underwear and night gowns off clotheslines.
On one occasion, the prowler, wearing a dressing gown, ran away after he was caught lingering in a resident's backyard.
Police were called to that scene and four finger and palm prints were taken from the rear door to the house.
It wasn't until December 2016 that three of those four 1988 prints allegedly matched Mr Edwards' 1990 prints on the national database.
Mr Edwards was arrested that same month, and charged with the murders of Ciara Glennon and Jane Rimmer, as well as the Huntingdale attack and an abduction and rape at Karrakatta Cemetery in 1995.
New details and allegations surrounding the fingerprints were put forward by prosecutors as proposed evidence on Tuesday during Mr Edwards' pre-trial directions hearing.
Lead prosecutor, Carmel Barbagallo, also alleges foot impressions were found at the same Huntingdale home.
"It was found that he [Mr Edwards] could not be excluded from making those foot impressions," she said.
Justice Stephen Hall, who will preside over Mr Edwards' judge-alone trial in July, pointed out that all of the allegations made by the state during the directions hearing were just assertions, and no evidence had yet been presented to the court.
The prosecution and defence will spend the hearing arguing the admissibility of some of the state's proposed evidence.
Mr Edwards has pleaded not guilty to all charges against him, including the Huntingdale attack, Karrakatta rape and Claremont murders.
On Tuesday, Ms Barbagallo revealed Mr Edwards' legal team may plan to challenge the integrity of the proposed DNA evidence against Mr Edwards.
His lawyer, Paul Yovich, told Justice Stephen Hall: "There is a primary issue in counts one, two, three, four, five, six, seven and eight, and that is who did it".
"In [the murder] counts, identity is the primary if not the only issue," he said.