Duke Behnke

USA TODAY NETWORK-Wisconsin

Evidence from the 2007 homicide trials of Steven Avery and Brendan Dassey remains in storage in Manitowoc and Calumet counties should it be needed for further testing or a new trial.

Avery and Dassey were convicted of killing 25-year-old photographer Teresa Halbach in 2005 in Manitowoc County. They were sentenced to life in prison, but both men have appealed their convictions.

Avery's defense team asserted during his trial that he was framed by Manitowoc County sheriff's deputies, and Avery's most recent appeal alleges evidence was obtained illegally and that the jury pool was tainted. Dassey's defense team asserts in U.S. District Court that his confession was coerced.

Interest in the criminal case has skyrocketed following the release of the Netflix documentary series “Making a Murderer,” which raises doubts about the validity of the convictions.

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Manitowoc County Clerk of Courts Lynn Zigmunt said 501 pieces of evidence were marked as exhibits during the Avery trial. They include photographs, video and audio recordings, diagrams, phone records and tangible items like the key to Halbach's sport utility vehicle. They also include biological items like Halbach's bones and a vial of Avery's blood that was central to the case.

The Dassey trial had 232 exhibits.

Chapter 72 of the Wisconsin Supreme Court rules state that for Class A felonies like first-degree intentional homicide, case files must be kept for 75 years after the final judgment.

Zigmunt said exhibits that can easily be stored in boxes, like paper documents, photographs and CD recordings, are kept in a locked evidence room at the Manitowoc County Clerk of Courts office. All DNA evidence and larger items like Halbach's SUV are in the custody of the Calumet County Sheriff's Department, the investigative and arresting agency.

“We don’t have space here to keep large exhibits," said Roberta Brice, a Manitowoc County deputy clerk of courts who handles criminal proceedings. “For all of the big evidence that we can’t keep here, the chain of custody went back to Calumet County for storage."

Lt. Mark Wiegert of the Calumet County Sheriff’s Department said evidence in the case was placed in secure storage according to proper procedures. Wiegert, one of the lead investigators in the Halbach homicide, declined to elaborate.

“I’m not really interested in getting into specifics on how we store evidence,” he told USA TODAY NETWORK-Wisconsin. “This case is no different than any other case."

TIMELINE: History of the Steven Avery case

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Duke Behnke: 920-993-7176, or dbehnke@postcrescent.com; on Twitter @DukeBehnke