MADISON (WKOW) -- A brutal murder of a young woman is still unsolved a decade later.
Monday marks 10 years since UW-Madison student Brittany Zimmermann was found stabbed and strangled in the middle of the day in her apartment in downtown Madison, just blocks from the Capitol. Her killer has never been found.
The brazen crime has left her family devastated, with no closure, and at the end of the rope.
"All 10 years I've asked, please let us know what happened that day," said her mother, Jean Zimmermann.
Memories are all the Zimmermanns have left, 10 years after their 21-year-old daughter was taken from them on April 2, 2008 in a home on Doty Street. Her parents Kevin and Jean have actively worked with Madison police to keep attention on the unsolved murder from several hours north in Marshfield.
Early on, they had hope.
"When you're told you're 99 percent sure that [the investigators are] on the right path and then all of a sudden you find out that path is the complete wrong path, now you're sitting back and thinking all these years wasted and this person's getting farther and farther away," said Kevin Zimmermann.
There were many ups and downs in the investigation in the past 10 years. 911 center operations were overhauled, after it was revealed a dispatcher mishandled Zimmermann's call for help where she can be heard screaming and struggling. Police were never sent to respond and the dispatcher shared inaccurate information with officials that wasted days of investigators' time. DNA evidence missteps also made for devastating setbacks over the years.
"Clearly there was a frustration on the part of everyone here at Madison Police Department when subsequent leads were run down to no avail, or that the evidence we had would have been tainted or unusable," Police Chief Mike Koval said. "There were roadblocks throughout all of this and as a result we've been sort of stuck ever since."
Koval inherited the unsolved case when he became chief in 2014. He says since the murder, the department has improved its investigative system. Koval called on a team of detectives to review the case when he took over as chief, rather than leaving the burden to one or two detectives who were becoming fatigued.
"We can have many sets of eyes questioning and challenging the same piece of evidence, looking at it from a different lens," Koval told 27 News.
In the past six months, a team has spent time developing new leads to explore in the case, according to Koval. The investigators have also recently re-submitted DNA evidence to the state crime lab. Koval says he's hopeful advancements in technology will bring the investigators closer to a suspect.
A DNA match discovered in the past two years led investigators to David Kahl, who was considered a material witness to the murder in the days after Zimmermann's murder. Chief Koval says at this time, the evidence is not enough for the district attorney's office to file charges. A man who claimed to know information that could incriminate Kahl died in a motorcycle crash in 2017.
"I don't view that as a squandered opportunity, in fact, some would argue that with his death now there might be people who are more willing to speak to us," Koval said about Scoles' death.
Koval says some may consider Kahl a suspect, but there is no legal burden of proof for police to bring charges. The Zimmermanns believe he had something to do with their daughter's death, but they say he may not have acted alone.
"I believe he had something to do with it, yes, there's no reason why his DNA would have been on her sweater," said Jean Zimmermann.
In 2016, Kahl told 27 News reporter Tony Galli that he was in Zimmermann's home the day she died, but he said he wasn't involved in her murder.
"I had a glass of water from her," Kahl said. "I can't remember if I shook her hand, gave her a hug, thanked her for loaning me the money."
The Zimmermanns can't wait any longer for the case to close. If the new DNA testing doesn't bring a tangible lead, they want an outside investigator brought in on the case.
"We've been beat down so many times you almost feel like a whipping post," said Kevin Zimmermann.
The couple has been in touch with a cold case investigator who they believe could solve the case if given access to the investigative files. That person would need complete access to records and DNA samples, which wouldn't be possible unless the case is deemed cold.
Koval says the department isn't ready to make it a cold case and releasing information now could compromise the integrity of the evidence, which could impact whether the DA could prosecute in the future.
"We don't think that we're done here and that's why it hasn't been relegated to a cold case at this point," Koval said.
It's frustrating for the Zimmermanns, but they're not giving up hope. They're still hosting fundraising events to support a local pet shelter in Brittany's name and have maintained a $40-thousand reward fund for information leading to a conviction in her murder. They've petitioned lawmakers to successfully pass a law to require DNA at arrest to bring more convictions in other investigations and the hope for answers in their case.
But their lives will forever be changed by the loss of their beloved daughter who had a lifetime ahead of her when she was killed.
"We've gotten more secluded. You don't like the social running around and we'd just rather be by ourselves a lot of times," said Kevin Zimmermann. "There isn't a day that goes by that you don't think about her."
The Zimmermanns say if Brittany were alive today she'd be a doctor, helping others. They hope her memory will live on as this case remains open.
"If [the public] would just spend a second in our shoes they would understand how difficult this has been for our family, to go through for the last 10 years, and it's time to bring Brittany some justice after 10 years of waiting."
If you were in the area of Doty Street on April 2, 2008 or if you know anything about that day, you're asked to call Madison Area Crime Stoppers at (608) 266-6014. Callers can remain anonymous. Police say any detail, no matter how small, could help in the investigation.
For more on this story: http://www.wkow.com/story/37833216/2018/03/28/monday-at-10-still-no-answers-10-years-after-murder-of-uw-student