Philip Cross

Philip Cross has been identified as the lead suspect in the December 15, 1984 rape and murder of 18-year-old Traci Hammerberg in Saukville, Wisconsin. The case has been cleared by exception due to the death of Cross. Hammerberg was last seen alive leaving a house party at about 12:30 am. It was about a four-mile walk in the winter cold, and she may have accepted a ride or met her killer along the road. Her body was found in a driveway in the snow that morning. She was naked from the waist down. She had been violently raped, her head was battered, and it was determined that she died of strangulation.

A DNA profile was developed from blood and semen that was found at the crime scene. The FGG investigation was conducted by Barbara Rae-Venter. She found a second cousin match to Cross and was able to build out the family tree. Cross’s DNA was confirmed as being consistent using samples that had been taken at his autopsy.

Philip Cross would have been 21 years old at the time of the crime. Cross and Hammerberg may have known each other, as they had ridden on the same school bus. Police stated that Cross had a violent criminal record, and a known anger problem. He may have become enraged had Hammerberg spurned his sexual advances. He died of a drug overdose in 2012.


Gene By Gene. “A Busy Month for Gene By Gene, Dr. Barbara Rae-Venter, and Law Enforcement.” PR Newswire (Press Release), November 21, 2019. Accessed December 13, 2020.

Madani, Doha. “35-Year-Old Cold Case Murder in Wisconsin Solved Using DNA and Genealogy, Police Say.” NBC News, October 22, 2019. Accessed December 13, 2020.

Pruitt, Sharon Lynn. “Genetic Genealogy Used to Crack 35-Year-Old Cold Case of Murdered Teen.” Oxygen, October 23, 2019. Accessed December 13, 2020.

Shapiro, Emily. “Man Who Allegedly Raped, Strangled Teen in 1984 Identified With Genetic Genealogy.” ABC News, October 20, 2019. Accessed December 13, 2020.


First Name Philip
Last Name Cross
Other Names
Victims 1 (Details)
IGG Started nd
Case Cleared 2019-10-22
IGG Org Gene By Gene


Case ID Name Age Case Opened Location Investigating Org Most Serious Charge Disposition Court
1284 Traci Hammerberg 18 1984-12-15 Saukville, WI Ozaukee CSO; FBI Second degree murder Case was cleared by exception due to death of perpetrator n/a

Last updated: February 9, 2024

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Case data and narrative licensed under CC BY 4.0: Dowdeswell, Tracey (2023), “Forensic Genetic Genealogy Project v. 2022”, Mendeley Data, V1, doi: 10.17632/jcycgvhm96.1. All other content, including photos, have been added.