Hunt for killer was an obsession for investigators

The hunt for Traci Hammerberg’s killer was a labor of love, if not an obsession, for the investigators who cracked the case.

For instance, former Ozaukee County Undersheriff Jeff Taylor had helped organize the investigation into her murder years earlier and came out of retirement to help finish the job, working on the case without pay, Sheriff Jim Johnson said.

“He did a lot of work,” Johnson said.

Neil McGrath, an agent with the state Division of Criminal Investigation, was assigned to the case in 2005, 20 years after Traci Hammerberg was raped, strangled and bludgeoned and her partially nude body was found in the driveway of a house on Maple Road in the Town of Grafton.

Some years later, he was transferred to narcotics, but he kept his hand in the quest to find her murderer.

“You get so far into it, I didn’t want to let it go,” McGrath said. “It was kind of a part-time thing for me and a lot of other people.”

It was McGrath who contacted the Los Angeles FBI Forensic Genetic Genealogy team this year to enlist their help. They had used a new method called forensic genetic genealogy to gather evidence in the Golden State Killer serial murder case that McGrath thought could help in the Hammerberg case. 

The original analyst with the State Crime Lab who worked on the case in the 1980s took the case file with her after she transferred to the Madison office, continuing to work on the case, officials said.

“Sometimes you get so involved in a case, it becomes a labor of love,” Dan Campbell, a Crime Lab supervisor in Madison, said after Tuesday’s press conference .

The other analyst is retired now and wishes to remain anonymous, he said, but has been following the case.

Johnson joined the case in 2005. He and McGrath were partners on the case and drove around the state interviewing people and collecting DNA samples.

“We spent a lot of windshield time driving around the state with a list of names,” he said.

A tremendous amount of resources were committed to solving a 35-year-old case.

Since March, after enlisting the help of the Los Angeles FBI office, Johnson and other investigators labored nearly every day for five months poring over genealogy databases and other sites to find a “familial match” with Hammerberg’s killer, using a conference room in the Sheriff’s Office as their command center.

Traci Hammerberg’s sister, Lorri Sell, now living near Omaha, said she was thankful that the Ozaukee County Sheriff’s Office and others never stopped searching for Traci’s killer.

“It’s never been a cold case because there were so many people for so long working on this,” she said.