Alison Dirr

USA TODAY NETWORK-Wisconsin

With 17 exonerations to her name, Steven Avery's new attorney isn't afraid to take on seemingly hopeless cases.

"She tends to take on cases that seem difficult or unwinnable on the surface, but when you dig into it, as she does, she finds the legal hook or legal axiom that needs to be presented publicly, which sometimes then changes the whole complexion of the case," said Rich F. Mallen, an Illinois attorney who first worked with Kathleen Zellner on a civil case in 2002.

Among the people Zellner has cleared is Ryan Ferguson, a Missouri man who was sentenced to 40 years in prison for a murder he didn't commit. He was freed in 2013 after she got key witnesses to admit they had lied under police pressure, according to Chicago Lawyer magazine.

A $100 million federal civil rights lawsuit is pending against the county, the prosecutor, the police and others, according to her firm's website.

She says she's confident she'll be adding Avery to that list.

On Tuesday, Zellner tweeted that she visited with Avery in prison: "He is identical to the other 17 innocent men we've cleared. Won't quit until he's out."

Those who have worked with — and against — Zellner describe her as a formidable opponent who comes prepared and fights for justice in cases few lawyers dare touch.

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Zellner, whose practice is based in Downers Grove, Ill., is the new lead attorney taking on Avery's case. She announced on Friday that she and Tricia Bushnell, legal director of the Midwest Innocence Project, would represent Avery in criminal matters.

Zellner did not respond to requests for comment, while a spokesman for the Midwest Innocence Project said Wednesday that Bushnell is not currently speaking with the press.

Avery and his nephew, Brendan Dassey, were convicted in the 2005 homicide of 25-year-old Teresa Halbach in Manitowoc County. Both men were sentenced to life in prison. A judge in Dassey's case set a parole eligibility date of Oct. 31, 2048.

The Netflix docu-series "Making a Murderer" turned the international spotlight on the cases of Avery and Dassey and highlighted allegations of police misconduct made in the case.

Doing the legwork

If her previous work is any indication, Zellner has probably already done a lot of digging on the Avery case, Mallen said.

For her, Mallen said, that means doing legwork that other attorneys might leave to an investigator or an associate.

In the civil case he handled with her, Chicago police had been sent to a home of a domestic violence victim but took too long to get there. They arrived after the woman had been shot and killed by her estranged husband.

The attorneys got the audio of the phone call from dispatch and then took an approach Mallen said helped synthesize the information for the court.

"We actually took a car, like a police car, followed the same route that the police officers could have — and should have — followed and got to the house," Mallen said. "And we timed it and then we had a video producer take the audio and show how if the police had just left in a timely fashion, followed their normal procedures, they could have gotten to her house long before she was shot and killed.”

They won a $4.25 million settlement for the estate of the woman who died, according to Mallen and news reports.

Karen Seimetz, who represented the city of Chicago in that lawsuit, described Zellner as a "fierce and formidable opponent."

"She'll go through a case with a fine-tooth comb," Seimetz said. "I think that's part of what makes her a challenge because she really knows the case and she will find every flaw that there is to find."

At the same time, though, Seimetz described her as very fair, professional, straight-forward.

In the interest of justice

Her work, though, is geared more toward justice than anything else, her colleagues said.

"I think she's a little different than a lot of attorneys that file these kinds of lawsuits," Seimetz said. "I think for her — her interest really is more in obtaining justice for her client and not a contingency fee for herself."

After one case, Seimetz asked Zellner to come in and explain the hallmarks of a false confession to some of the lawyers defending the city — Zellner's opponents. Most lawyers wouldn't be part of training their opposition, because they wouldn't want to give any of their strategy or secrets away, Seimetz said.

But Zellner made a presentation before 20 to 30 defense attorneys.

"I just think it just sort of says something," Seimetz said. "Maybe it gets back to her self confidence or really kind of what her overall objective is."

She takes on cases that are difficult and controversial, likely where she thinks she can do some social good, said James D. Montgomery, who has worked with her on a couple cases, including the 2002 civil case.

"The conscientiousness with which she represents and cares about her clients has always made her a heroine for me," he said.

She doesn't take on just any case.

Zellner must be convinced of the person's innocence and DNA evidence must play a central role in getting to the truth if she's going to take a case, the Illinois State Bar Association wrote.

As for the Avery case, it seems right up her alley, Seimetz said.

"The series obviously highlights some rather questionable goings-on and that is the sort of thing that would pique her interest," she said.

Alison Dirr: 920-996-7266 or adirr@gannett.com; on Twitter @AlisonDirr