Police are calling on Canberrans to combat the "decay of information" in the territory's old cases, warning that the passage of time is investigators' greatest enemy in the search for long-term missing people.
In recent years, ACT Policing have received limited information about the disappearances of Amelia Hausia (missing since 1992), Elizabeth Herfort (1980), and Megan Mulquiney (1984).
In a bid to fight fading community memory, police partnered with local artist Harriet Mitchell to spotlight the cases through three commissioned portraits and help inspire new information.
Detective Sergeant Craig Marriott, head of the unsolved homicide and long-term missing persons units, pointed to the "decay of information" as witnesses assume their own memories are trivial.
"It may be the most innocuous piece of information that gives us a lead that allows us to dig a little," he said.
When asked what viable tip could lead to investigative breakthroughs, he said a casual chat from decades ago could contain a clue about a missing person's intentions or reveal a mutual friend police have not spoken to.
"Even as simple as ... 'I knew her and I saw her a week before and we bumped into each other at the shops and we chatted for five minutes'," Detective Sergeant Marriott said.
"We don't know what we don't know," he said.
The three portraits, created over three months by Ms Mitchell, 30, aim to do what traditional police files cannot and inspire a deep empathy needed to trigger long-forgotten memories.
Although Ms Mitchell has never had a missing person in her own life, she spent months living with the stories of the three girls, and found herself connecting to familiar details from circumstances surrounding their disappearances.
"When I was Megan's age, I was also working at the Woden Plaza," Ms Mitchell said, noting that walking the same spaces bridged the decades between them.
Megan Mulquiney was 17 years old when she vanished without a trace on July 28, 1984. She had just finished her weekend shift at Big W and was last seen at the Woden bus interchange where she usually took the bus home.
Amelia Hausia was the same age when she went missing on December 22, 1992. She was sighted at the Woden Plaza five days after her family last saw her, upset after a fight with a boyfriend.
"Amelia being the same age as my sister is currently, that was something that I couldn't ignore while painting, and gave an instant connection to her," Ms Mitchell said.
With Elizabeth Herfort, who went missing from Civic after a night out at the Australian National University bar on June 13, 1980, the connection was maternal.
The 18-year-old went to the same local bar the artist's mother frequented the same year.
"Thinking about the fact that now Elizabeth would have been the same age as my mother, and the life my mother has had ... was also a source of this depth and sadness," Ms Mitchell said.
Leading Senior Constable Colleen McKillop, who serves as a vital point of contact for the families of Amelia, Elizabeth and Megan, said they have endured agonising uncertainty for decades.
"It's a grief that has no resolution," she said. "It's ongoing and deeply felt. So it's relentless."
Leading Senior Constable McKillop coordinates support on the families' own terms, with some wanting regular contact every three months, and others only wishing to hear of concrete developments.
"More than anything, they want to know that their loved one is not forgotten, that the cases are still active," she said.
