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2-Apr-2025
Wisconsin v. David Kahl - closing the Brittany Zimmermann cold case
In 2008, 21-year-old University of Wisconsin student Brittany Zimmermann was found brutally stabbed and strangled in her Madison home. Prime suspect David Kahl had long been on investigators’ radar. But crime labs often cannot interpret their DNA data. The evidence from Zimmermann’s clothing was too "limited" for them to handle.
The Madison Police Department turned to Cybergenetics, and the case turned. TrueAllele's math engine easily separated the four- and five-person mixtures into probabilistic genotypes. Comparing them with Kahl's DNA, our computer immediately identified Kahl on five items of victim clothing. After a decade of forensic failure, TrueAllele found the first definitive DNA link.
Kahl pleaded guilty in 2022. He was sentenced in 2023 to life in prison without parole.