Norm Gahn (right) confers with former longtime Milwaukee County prosecutor Mark Williams in a 20-year-old homicide cold case in 2012. Gahn, who pioneered the use of DNA evidence in criminal prosecutions in Wisconsin, is the first winner of the State Bar of Wisconsin’s Lifetime Legal Innovator award. Credit: Journal Sentinel files

SHARE Norman Gahn, who pioneered the use of DNA evidence in criminal prosecutions in Wisconsin, is the first winner of the State Bar of Wisconsins Lifetime Legal Innovator award. Andy Manis

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The State Bar of Wisconsin decided to give out a new award this year, Lifetime Legal Innovator. The first winner seemed an obvious choice.

Norman Gahn pioneered the use of DNA evidence in criminal prosecutions in Wisconsin, a staple of the process now, but a novel, exotic and risky ploy when he began explaining it to Milwaukee County jurors in the late 1980s.

Gahn gained a national profile a decade later when he used the improving science to charge unnamed serial rape suspects before the statute of limitations expired on those crimes. And just last year, he charged another state first — a defendant identified through matches of his close family's DNA.

"I was caught off guard, but it's a nice award. I was very pleased," Gahn said, quickly sharing credit with the state's crime labs in Milwaukee and Madison.

"They're so cooperative, so helpful, and taught me so much," he said. "I couldn't have done anything without them."

Tom Watson, a lawyer, chaired a committee looking for "risk takers, visionaries in the legal profession who found creative ways to solve client or community problems.... Attorney Gahn epitomizes the essence of that concept."

Watson said Gahn's recognition got the lifetime tag for his work's long-term impact.

Gahn, 68, retired in June after 31 years with the Milwaukee County district attorney's office. He'd been on the job three or four years when DNA started to emerge as a crime-fighting tool. While the science may have intimidated or bored many prosecutors, Gahn almost immediately saw potential, perhaps because of his background. While serving in the Army before law school, he had earned a master's degree in forensic science at George Washington University.

He remembers the first sample he sent to a private lab: blood on a stuffed toy donkey found where an elderly woman had been asphyxiated, one of several similar victims in a case without many other clues.

The lab produced a DNA profile from the blood, and when it later matched that of a suspect developed on some other evidence, it was enough to charge Robert Wirth, who was ultimately convicted of four murders.

"Right after that, cops started flooding us with cases with blood and semen, but no suspects," Gahn recalled with a chuckle.

"Cases we could not charge, now we could, like sexual assaults when the victims misidentified the suspect at a lineup. It really changed things."

Case earns national profile

About a decade later, Gahn tried something that earned him a national profile and led to a change in state law. Faced with the six-year deadline to charge several unsolved rape cases from the 1990s, Gahn issued warrants against the DNA profiles from semen taken from victims.

"The law says you could issue a warrant if you could ID the subject with reasonable certainty," he said. "A DNA profile is even more certain than a name."

At the time, states had begun gathering DNA samples from felons into growing databases. The idea was that through regular computer comparisons between the John Doe DNA profiles against the known DNA profiles, investigators would eventually match them to a name.

And they did. In 2001, John Doe No. 12 became Bobby Dabney. He was convicted, an appeals court upheld the "no name warrant" that charged him and suddenly everyone took interest. Gahn began going around the country to speak with law enforcement and prosecutor groups.

Gahn said half of the 24 DNA John Does have been charged, and he thinks the rest might still get identified, as the computers keep running the profiles against the growing databases of known DNA.

The practice stopped at 24 because in 2002, the Legislature, convinced of the accuracy of DNA, changed the statute of limitations for sexual assaults. Now, prosecutors have a year from whenever a suspect's DNA matches a named sample to file charges.

Last year, Gahn led another novel use of DNA. Police had the same DNA evidence from sexual assaults in 2002, 2008, 2011 and 2012. It wasn't matching any known samples, but advanced DNA analysis is providing ever sharper profiles, kind of like TV images improving with high definition and 4K technology. That allowed investigators to identify people who were likely close relatives of the attacker.

With that vastly narrowed set of possible suspects, detectives were able to find Michael L. Dixon within 24 hours. He was convicted of two of the assaults this year and sentenced to 45 years in prison.

Gahn enjoys spending more time with family now and "figuring out" retirement. He remains active with a National Institute of Justice committee working on protocols for getting sexual assault kits tested promptly, and said he expects to start teaching part-time soon, probably encouraging more young lawyers to become prosecutors.

"In 31 years, there was nothing better than getting up every day to seek truth and justice. I loved every minute of it."