If you remember the Emmy Award-winning documentary series “Making a Murderer,” you know there is good reason to suppose that the defendants, Steven Avery and Brendan Dassey, were wrongfully convicted of the murder of Teresa Halbach. As the documentary showed, Attorney Dean Strang and I represented Avery at trial.

Recently, Kathleen Zellner, the current attorney for Avery, won an appellate motion. Ultimately, the win could lead to a new hearing, a new trial or a reversal of his conviction.

Attorney Zellner had previously moved to have certain evidence DNA tested with a newly developed type of DNA test — a number of suspected burned human bones that might have belonged to the victim.

The bones were recovered by searchers in a quarry and gravel pit some distance away from the Avery Salvage Yard. At the time of the trial, the State’s pathologist could not conclusively identify them as human, and DNA tests were inconclusive. Yet the pathologist admitted there was a pelvic bone that was possibly human.

The defense argued at trial that if they were Halbach’s bones that supported the belief that her body was not burned behind Avery’s garage, as the State argued. We argued the primary burn site was elsewhere, perhaps in the quarry where these bones were found. If the body was burned somewhere else, then Avery was not guilty, because no one would burn a body someplace and them deliberately dump the cremains in their own back yard.

The State did not disagree with this logical argument, but instead argued they were only “possibly human,” and thus had no relevance to this murder.

The bones were supposed to be preserved as biological evidence by the State. Wisconsin has a “biological evidence preservation” law which requires the police to retain any such evidence for as long as a person connected with the crime is in custody — in Avery’s case his entire life, since he is not entitled to parole. The purpose of the law was that new scientific tests could be developed — as DNA was — that might exonerate the wrongly convicted.

However, Attorney Zellner recently discovered a previously undisclosed report that said the prosecutors and investigators gave all of the bones to the Halbach family in 2011, even while Avery’s first appeal was still pending. No notice was ever given to Avery or his lawyers so that they could object.

This decision was very curious, because the State argued at trial the quarry bones were not even human, much less Teresa Halbach’s remains. Why would the State have given the family non-human bones to comingle with her remains, unless there was reason to believe the State’s claim at trial that the bones were not human was false, and the bones really did support the defense?

After discovering this hidden report, Attorney Zellner asked the Wisconsin Court of Appeals to return the case to the circuit court to determine how and why this potentially exculpatory evidence was essentially destroyed by withdrawing it from police custody and giving it to the Halbach family for disposal.

Turning this crucial evidence over to the family violated a U.S. Supreme Court case called Youngblood v. Arizona, which involves the state’s duty to properly preserve potentially exculpatory evidence. It also violated the state’s biological evidence preservation law.

The Wisconsin Court of Appeals remanded the case back to the circuit court that originally heard the case. That court could grant a hearing to find out what happened to the exculpatory evidence and why it was destroyed. The court would have to consider whether the evidence was destroyed by the State in “bad faith,” perhaps to preclude Avery, if he were ever granted a new trial, from supporting his argument that the primary burn site was elsewhere.

That very outcome occurred in a prior case of mine, State of Wisconsin v. Ralph Armstrong, after my client was wrongly imprisoned for 29 years.

After this win, Avery was given 14 days to file his additional postconviction motion in the trial court raising the destruction of bone evidence issue. That judge will then decide whether to grant a hearing. We will report further developments in this blog.