Brendan Dassey faces crucial hearing Tuesday before federal appeals court

CHICAGO - Brendan Dassey’s lawyers have racked-up some monumental victories in the past 13 months.

They laid the groundwork for a federal judge to overturn Dassey’s conviction in the 2005 murder of Teresa Halbach — a ruling that was later affirmed by a federal appeals panel.

But there have been setbacks as well.

Dassey’s attempts to be freed from prison on conditional bond were rebuffed and, more importantly, the full U.S. Court of Appeals for the Seventh Circuit in Chicago decided last month to re-hear the case, which was prominently featured in the Netflix docu-series “Making a Murderer.”

Oral arguments will be held on Tuesday. The court’s ruling — which is a virtual lock to be appealed to the U.S. Supreme Court — could ultimately determine whether Dassey will be re-tried, released from prison, or serve out his life sentence.

The key issue is whether detectives coerced a confession from Dassey, who was 16 at the time of Halbach’s murder, or if they acted within the scope of proper police procedure.

“The full court could go either way,” said former Wisconsin Supreme Court Justice Janine Geske.

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On Aug. 12, 2016, U.S. Magistrate Judge William Duffin, who is based in Milwaukee, overturned Dassey’s conviction, ruling that investigators made “repeated false promises” that rendered his confession to the crime involuntary.

The Wisconsin Department of Justice appealed, and, on June 22, a three-judge panel at the Seventh Circuit affirmed Duffin’s ruling by a 2-1 margin.

But that didn't settle the issue. In early August, the Seventh Circuit granted a request by the state justice department to have the entire panel of judges rehear the case. It is known as an “en banc” review.

“It's hard to know exactly what to make of en banc review, beyond that several of the judges on the Seventh Circuit have doubts about the correctness of the decision of the three-judge panel,” said Michael O’Hear, professor of law at Marquette University Law School.

Geske agreed, saying it’s difficult to assess why the full court decided to review the case.

“(The outcome) is hard to predict,” she said. “But my guess is they probably uphold (Duffin’s) decision.”

Regardless of which way the Seventh Circuit rules, an appeal to the U.S. Supreme Court is virtually certain, said Raymond Dall’Osto, a Milwaukee attorney with a specialty in criminal defense.

But he said it would be unusual for the nation’s highest court to take the Dassey case.

“Those (petitions for review) are rarely granted,” he said.

Dall’Osto said he is hoping that Dassey will prevail before the Seventh Circuit.

“If (the judges) follow the law as applied in this case … the conventional wisdom would be affirmation,” he said.