The serial killer made little effort to hide his tracks. Over the course of a year in the 1970s, he dumped the remains of four young women in different spots — along a road, in a gravel ditch, beneath an underpass — just outside Calgary, in Western Canada.
They were fully clothed, all had been strangled and DNA evidence revealed that they had been sexually assaulted.
Still, it took nearly 50 years and filtering through 853 possible suspects for Canadian police on Friday to finally reveal that the women had been the victims of a serial killer.
The police identified their killer as Gary Allen Srery, who had fled to Canada while out on bail in 1974 after being charged with rape by the police in Los Angeles.
He died at 68, of natural causes, in an Idaho prison in 2011, where he was serving a life sentence for a rape in that state. The authorities believe he may have killed other women in Canada and the United States.
Despite Mr. Srery’s brazenness, there were few witnesses to the killings, which were committed in 1976 and 1977.
The investigation dragged on for several decades. In the 1990s, four separate task forces combed through leads, including roughly 800 tips and 500 statements from the public, Supt. David Hall of the Royal Canadian Mounted Police said during a news conference in Edmonton on Friday.
“No investigation, no matter how successful, could undo the harm caused by crimes of this nature,” Superintendent Hall said. But, he added, the perseverance of investigators over many years “allows us to bring answers to the families of the four young women robbed of their futures.”
Three of the four victims were teenagers.
Eva Dvorak and Patricia McQueen, both 14, were visiting friends after school on Feb. 15, 1976, and were last seen together around midnight. Their bodies were found less than 12 hours later, in an underpass.
Seven months later, in a gravel ditch just west of Calgary, the police found the body of Melissa Rehorek, 20, one day after she had gone missing. Ms. Rehorek, a hotel housekeeper, had told her roommates that she was going to hitchhike to the mountains before she disappeared.
Five months later the police found Barbara MacLean, 19, a bank worker who had gone out with friends to a cabaret show at a bar in Calgary. Witnesses last spotted her walking home from the bar in the early hours of Feb. 26, 1977.
A dog walker stumbled on her remains, which showed signs that she had fought back against her attacker, the police said.
Semen was found on all four victims, but, at the time, investigative tools to analyze it were limited. It was not until 2003 when lab tests were able to link the same unknown offender to the DNA samples found on two victims, Ms. Rehorek and Ms. MacLean.
A break in the case came with the help of genetic genealogy, a forensic technique that uses DNA samples to identify relatives of a suspect and home in on them. In 2022, DNA from the killings of Ms. Dvorak and Ms. McQueen was used to link all four killings to the same man, Mr. Srery.
By the time he arrived in Canada in the mid 1970s, Mr. Srery was already a convicted rapist in the United States.
Detectives are now piecing together a detailed timeline of Mr. Srery’s life, tracing his movements between 1979 to 1998. His transient lifestyle, the nine aliases he used and his violent history suggest to the police that he may have committed other killings.
“We truly believe the suspect is not involved in only four homicides, but there’s a distinct possibility that he’s responsible for many more, either in Alberta, British Columbia, or the western United States,” Staff Sgt. Travis McKenzie, a commander with the Mounties’ historical homicide unit, told reporters.
Mr. Srery was never questioned in connection to the investigation of the Calgary killings. However, he was convicted in Canada in another rape case in 1998 — in New Westminster, British Columbia — and then deported to the U.S. in 2003.
Because Mr. Srery is dead, the police provided relatives of the victims a detailed presentation of their findings and what led them to zero in on Mr. Srery, Staff Sergeant McKenzie said in an interview.
“I know they’re appreciative and they’re grateful,” he said, “but I also know for a fact that their grief has never stopped either.”
Mr. Srery was born in Oak Park, an affluent suburb of Chicago, and then moved to California with his family and three younger siblings, the authorities said. He married in 1960, had several children and was divorced in 1969.
Genetic genealogy has become a more common technique among law enforcement to try to solve cases that have long grown cold. But its use is limited in Canada because the labs needed to do that kind of work are largely in the United States.
“In light of the growing demand for genetic genealogical testing in Canada, we need to re-evaluate where we’re doing that work,” said Nicole Novroski, a forensic geneticist and professor at the University of Toronto. “It truly is an incredibly powerful tool.”
