POSTED: Wednesday, November 17, 2010 -- 5:30 p.m.
By NBC15's Dana Brueck
The Dane County Sheriff says an internal investigation has revealed evidence from two old murder cases has been destroyed.
Twenty-year-old Julie Speerschneider was last seen alive in March of 1979.
Two years later... a 16-year-old boy found her skeletal remains.
Now, Dane County Sheriff Dave Mahoney says evidence from the unsolved case was destroyed.
"Knowing what we know today, having spent 25 years as a detective working on several homicide cases, um, it's very unfortunate."
It didn't happen under his watch, but he knows the loss makes solving the cold case more of a challenge.
An internal investigation, started in April and with help requested from UW Police, has revealed several items from the Speerschneider case were destroyed in 1981, '88 and '93.
Evidence from another murder, the murder of Shirley Stewart, also was destroyed in 1988... with the written documentation to prove it.
"Everything points to human error. I truly believe that had the individuals involved known these items clearly were items of evidence from a homicide, I would surely hope that evidence would not have been destroyed," Mahoney says, "They don't even recall destroying the evidence."
The two individuals responsible no longer work for the sheriff's office, which began the audit of its evidence after a public records request.
Mahoney says while the number of items lost is small, they could've possibly proven valuable.
"Some of it potentially could be DNA evidence."
Those in charge of the investigation say this is where evidence was kept back in the '80s.
This locked closet housed evidence from homicides.
The sheriff says a timeline shows the evidence largely was destroyed when the room underwent an expansion... which only meant additional space in the room next door.
This is one of the office's current evidence rooms.
He says today's safeguards, including bar codes and restricted access, prevent something similar from happening again.
"Even I don't have access because there's really no reason for me to have that kind of access."
The sheriff adds investigators have found new leads as part of the internal investigation.
He also says investigators have been unable to locate evidence from the 1968 murder of Christine Rothschild, but there's no record of the evidence being destroyed.
With grant money from the Wisconsin Department of Justice, the sheriff's office is actively investigating a cold case from 1978.
Tune into NBC15 News at 10 p.m Wednesday to see the report as detectives seek new leads to solve the 32-year-old mystery.