Andy Thompson

USA TODAY NETWORK-Wisconsin

When "Making a Murderer" takes a step back from the national spotlight — and there's no telling when that might happen — convicted killer Steven Avery won't fade from the public's view.

Avery, who is serving a life term with no possibility of parole for the 2005 murder of Teresa Halbach, has vowed to keep fighting the conviction in the appeals courts, a process that could go on for several years and involve a variety of court venues.

"I ain't gonna give up," Avery said near the end of "Making a Murderer," a 10-part docu-series released by Netflix in mid-December. "When you know you're innocent, you will keep on going. The truth always comes out sooner or later."

Since being sent to prison in 2007, Avery's attempts to overturn the conviction have failed. The court of appeals affirmed the jury's guilty verdict, and the Wisconsin Supreme Court refused to hear his case.

The same rulings came down against Avery's nephew, Brendan Dassey, who also is serving a life sentence for his role in Halbach's slaying. Dassey has a case pending in federal court in which he alleges that his constitutional rights were violated, his confession was coerced and that his pretrial attorney was disloyal. There is no timetable for the judge's ruling.

Avery has yet to file a federal appeal, but he has sought relief on multiple occasions from the trial court and the state appeals court. His most recent court filing was on Jan. 7, when he claimed that his property was illegally searched and that any evidence gathered as a result can’t be used against him.

That case is separate from any appeals that his new team of attorneys, headed by Kathleen Zellner of Downers Grove, Illinois, will file in the future.

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Timeline: History of the Steven Avery case

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New evidence key to reconsideration

While there are long-established guidelines in place for appeals, there is no limit on the number of times that a convicted criminal can file for consideration — or reconsideration — by the courts, legal experts say.

Everyone convicted of a crime has a right to a ruling by the state’s court of appeals. Some opt to ask the trial judge to review the matter first. Defendants who lose in the court of appeals can petition the Wisconsin Supreme Court or the U.S. Supreme Court to review the case, but few cases are accepted by the high court. The federal system is another venue for defendants who claim that their constitutional rights were violated.

Filing for post-conviction relief is an ongoing option for defendants, but those issues are narrowly focused to include newly discovered evidence or issues that weren’t previously addressed by appeals courts. An example is a DNA test that points to a defendant’s innocence that wasn’t available at the time of trial. Or a potentially important issue that hasn’t been raised previously and could change the jury’s decision.

“You can’t just keep filing (the same) motions over and over again,” said Keith Findley, a University of Wisconsin Law School professor and co-founder of the Wisconsin Innocence Project.

Michael O’Hear, a professor of law at Marquette University Law School, said the appeals process is complex.

“In theory, a defendant gets one appeal and one appeal only. However, there are a variety of exceptions, for instance, in the case of newly discovered evidence showing the defendant’s innocence,” O'Hear said. “Also, if a defendant received incompetent representation the first time around, then there might be an ability to pursue a new appeal.

“There is no strict numerical limitation on these things, but the standards for reversing a conviction are high, and there are a lot of procedural hoops a defendant has to jump through in order to get a court to take another look at the case after the first appeal is over.”

Findley’s team at the Wisconsin Innocence Project paved the way for Avery’s release from prison in 2003 when it was scientifically proven that Avery did not commit a rape for which he served 18 years in prison. Two years later, Avery was charged with killing Halbach. The Innocence Project is not working on the current Avery case.

Findley disagrees with critics who say prison inmates should have limited appeal rights.

He said the “lock-‘em-up-and-throw-away-the-key mentality" makes him cringe. Findley pointed out that advances in DNA testing over the years has shown that the criminal justice system is fallible.

"You can never be too sure,” he said. “Sometimes, conclusive evidence surfaces that people (who were convicted) are innocent.”

Findley said the justice system is based too much on “finality,” when it should be more receptive to getting things right — even if that means looking at old cases again.

Milwaukee attorney Raymond Dall’Osto said it’s important to have an avenue for reconsideration in case vital new evidence surfaces in a case.

“We are a human system,” he said. “Humans can sometimes make wrong judgments or judgments based on facts that change.

“In my view, unless and until the human race becomes omniscient and infallible, there should always be a means, or safety valve, for a convicted person to raise new and meritorious facts and arguments in court in order to seek relief from (a) criminal conviction and sentence — even if they have exhausted all regular appellate routes.”

Andy Thompson: 920-996-7270 or awthompson@gannett.com; on Twitter @Thompson_AW