Playing cards depicting victims of cold-case murders have been given to NSW prisoners in the hope the initiative will help crack cases.
Each playing deck, which were produced by inmates working in Corrective Services Industries, contains cards featuring photographs and information about 52 unsolved homicide cases or suspicious disappearances.
Homicide Squad commander Danny Doherty said it was hoped the cards would generate new leads by circulating crucial information about suspected victims among inmates who might have knowledge of the crimes.
"This format has already had success in the United States and other jurisdictions here in Australia," he said.
"Inmates often share details of their crimes or those committed by associates with others.
"This is about capitalising on that and generating new information to progress these cases."
Police Minister Paul Toole said the initiative had been planned in close consultation with the victims' families.
"The police investigations into these cases are well and truly active, but they are reliant on information that has been held tightly for too long," he said.
Homicide Victims' Support Group executive director Martha Jabour said more than five years of advocacy had led to the program.
"The families of those represented were personally involved in the production process because for them, these cards represent the potential for both truth and justice," she said.
Crime Stoppers NSW chief executive Peter Price said the initiative reinforced the importance of how sharing information helped solve crimes.
"Crimes aren't solved with one piece of information but that one fact - no matter how small or insignificant it may seem - could be the vital clue police need to solve a crime," he said.