After almost 35 years of Wisconsin police have identified the man who raped and killed 18-year-old Tracy Hammerberg.
15 Dec 1984 Topless Tracy’s body found in the driveway of a house in Grafton.
On Tuesday, 22 October 2019, the police said, using the evidence of DNA and forensic genealogy, they determined that Hammerberg, raped and strangled 21-year-old Philip Cross, who died from a drug overdose in 2012.
Photo: Ozaukee County Sheriff’s Office
That night Tracy was at a party in a neighboring town, where the night decided to get home by walking almost 4 miles.
During the investigation, the police collected the suspect’s DNA from the girl’s body – semen and blood under her fingernails. The County Sheriff’s office Ozaukee investigated over the past 34 years. Helped police and the Department of behavioral analysis FBI, which provided a criminal profile.
Was interviewed hundreds of witnesses, and more than 400 people were excluded from the group of suspects through the analysis of blood group and DNA.
In March 2019, the investigators turned for help to a group of forensic genetic expertise of the FBI in Los Angeles, which previously helped to identify the serial «Killer Golden state» , California.
The DNA profile was uploaded to the database of genealogical data. The investigators constructed an extensive family tree, trace four generations. Then, they determined the men, who ranged in age from 16 to 60 years old in 1984.
This process has led to the fact that the police have identified Cross as a potential suspect on August 28 this year. When Cross, who has repeatedly been arrested, died from a drug overdose in 2012, the Department of medical examination Milwaukee County received his DNA profile.
In the end, the State crime lab in Madison have determined that the DNA profile of the Cross matched the samples taken from the body of Tracy.
Cross was never questioned in this case.
«We wanted justice for Tracy and her family, said County Sheriff Ozaukee, James Johnson. — We became her voice when she could no longer speak.»
