27 News has uncovered Madison police officials consider sex offender David Kahl a “material witness” in the death of UW-Madison student Brittany Zimmermann, and have asked Kahl to help them find two homeless men.
In court documents filed by a Wisconsin Department of Corrections probation agent, Zimmermann’s April 2 murder is cited in a request to revoke Kahl’s probation. “Mr. Kahl was a material witness in the death of a coed that was discovered on Doty St.,” wrote agent Allen Matheus.