A Back Bay murder mystery that has haunted Boston for more than four decades may finally be nearing a legal conclusion. Prosecutors say 71-year-old John Irmer, who confessed to a 1979 killing in the neighborhood, is expected to change his plea this week in Suffolk Superior Court in the death of 24-year-old Susan Marcia Rose. The case was revived after Irmer walked into an FBI field office and admitted involvement, and investigators say DNA testing later linked him to evidence preserved from the crime scene, potentially delivering long-sought answers to Rose’s family and cold-case detectives.
According to NBC Boston, Irmer is scheduled to appear in court on Wednesday for a formal change-of-plea hearing. Prosecutors allege he told federal agents in 2023 that he struck Rose in the head with a hammer and then raped her inside a Beacon Street building that was under renovation at the time.
How investigators tied him to the case
Prosecutors say investigators corroborated Irmer’s story after his conversation with FBI agents by collecting a DNA sample that matched material preserved from the 1979 scene, according to the Suffolk County District Attorney's Office. The DA’s release states that authorities in Portland, Oregon, arrested Irmer as a fugitive following his confession and later transported him to Boston for arraignment.
The 1979 scene and earlier trial
Contemporaneous coverage and court records report that Rose’s partially nude body was found on Oct. 30, 1979, inside 285 Beacon St., a building then under renovation. She had suffered multiple blunt-force skull fractures and brain lacerations, according to The Boston Globe. The Globe and prosecutors note that a different man went on trial for the killing in 1981 and was acquitted, leaving the case unresolved for decades. “This was a brutal, ice-blooded murder,” Suffolk County District Attorney Kevin Hayden said in the office’s 2023 statement, as described in the DA’s release.
Why the confession surfaced
Authorities say the breakthrough came in 2023, when Irmer walked into an FBI field office in Portland and voluntarily confessed. Follow-up investigative work there, along with DNA analysis, led to the reopening of the long-dormant file. Local reporting from WCVB notes that prosecutors highlighted Irmer’s criminal history, saying he had already served about 30 years in California for a separate homicide and told agents he had confessed to another killing in a southern state.
What’s next in court
Prosecutors say the expected change of plea in Suffolk Superior Court could finally resolve a homicide that has weighed on Boston investigators for more than forty years, according to NBC Boston. If Irmer formally pleads guilty, a judge will then schedule sentencing and any related victims’ rights proceedings in the weeks that follow.
Legal context
Irmer faces charges including first-degree murder and aggravated rape, felonies that in Massachusetts can be prosecuted regardless of how much time has passed and that carry some of the state’s most severe penalties, according to state legal summaries. For additional background on prosecution timelines and statutes governing sexual offenses, see Mass.gov and other legal overviews of limitation rules. The DA’s office and future court filings will determine the precise sentencing exposure if a guilty plea is entered.
