The lead investigator of the infamous murders at Glensheen mansion has died.
Gary Waller died Tuesday at age 72, the St. Louis County Sheriff's Office said in a news release.
Waller served 21 years with the Duluth Police Department, during which time he investigated the brutal 1977 killings of 83-year-old Elizabeth Congdon and her night nurse in Duluth's Glensheen Historic Estate.
Waller died at his home in Moose Lake, but a cause of death has not been released.
The Duluth News Tribune notes he had been sick and wasn't able to attend the events surrounding the 40th anniversary of the Glensheen murders back in June.
Waller had spoken many times publicly about the investigation, and he even co-wrote the book Will to MurderwithJohn DeSanto, the chief prosecutor at the time, about the investigation and prosecution of the suspects in the case.
Officials always suspected Congdon's adopted daughter and her husband, but the daughter was never convicted. Read more about that here.
Waller served as the sheriff of St. Louis County from 1987 until he retired in 1999. During his tenure, Waller was a member of the Minnesota Sheriff's Association, serving as president for a term, and in 1995 he was awarded the FBI Director's Community Leadership Award.
"Gary Waller made our agency more progressive. He brought in new policies and new ways of doing things," current Sheriff Ross Litman said in a statement. "Because of his background, he strongly supported investigations and brought a modern ethic and new direction in the way we do our work."
The sheriff's office says Waller improved the way investigations are conducted, built the current St. Louis County Jail and implemented the D.A.R.E. program for deputies to work in schools, to name "just a few" of his accomplishments.
A funeral is scheduled for Aug. 25. Honor guards from the St. Louis County Sheriff's Office and the Duluth Police Department will be present.