Police inspector Grete Lien Metlid and police attorney Henrik Rådal briefed about the breakthrough in the murder case. Credit: Even Haaland/Oslo police district
Knut Kristiansen, a 71-year-old linguist, was found murdered in his apartment in Sandaker, Norway on July 20, 1999.
There were no traces at the scene that indicated a break-in or illegal entry into the apartment. Based on the investigation, police believe that only Kristiansen and the perpetrator were present, and that Kristiansen let the person in.
Police had a difficult starting point, as Knut was found about two weeks after the assumed day the murder took place—July 4, 1999.
At the time, police secured DNA traces at the crime scene, which they believed must have come from one perpetrator. Analysis never produced a match in the DNA register, though.
In recent years, investigators made several attempts to identify the unknown DNA profile, but still no name.
When the police reviewed the case again in 2020, they had already started investigating the possibility of using genealogy databases for more indications of who the unknown DNA profile could belong to.
When the method was to be tested in a pilot project at Kripos, following a mandate from the Attorney General, the case was incorporated into a collaborative project with Oslo University Hospital and the National Archives.
Through genealogy and other investigative steps, the police finally managed to arrive at a likely suspect. The genetic investigation pointed in the right direction, and the actual breakthrough came when police found a match between the DNA left at the murder crime scene and that left of another case. It turns out the suspect was involved in another case of violence in a different police district. When they compared the DNA between the two scenes, it matched.
The perpetrator was a Norwegian man from Oslo who was in his mid-40s at the time of the murder. Police believe he did not live that far from Kristiansen at the time. The suspect died the year after the murder. Investigators do not know what relationship or acquaintance there was between the man and Kristiansen prior to the murder in July 1999.
This is the first time Oslo police used genetic genealogy as an investigation tool.