Steven Avery was born in 1962 in Manitowoc County, Wisconsin, to Allan and Dolores Avery. Since 1965, his family has operated a salvage yard in rural Gibson, Wisconsin, on the 40-acre (16 ha) property where they lived outside town. Avery has three siblings: Chuck, Earl, and Barb. He attended public schools in nearby Mishicot and Manitowoc, where his mother said he went to an elementary school “for slower kids”. According to one of his lawyers in 1985, school records showed that his intelligence quotient was 70 and that he “barely functioned in school”.

In March 1981, at age 18, Avery was convicted of burgling a bar with a friend. After serving 10 months of a two-year sentence in the Manitowoc County Jail, he was released on probation and ordered to pay restitution.

On July 24, 1982, Avery married Lori Mathiesen, who was a single mother. They have four children together: Rachel, Jenny, and twins Steven and Will.

In late 1982, two men admitted that, at Avery’s suggestion, they threw Avery’s cat “in a bonfire and then watched it burn until it died”, after Avery had poured gas and oil on it. Avery was found guilty of animal cruelty and was jailed until August 1983. “I was young and stupid, and hanging out with the wrong people”, Avery said later, of his first two incarcerations.

In January 1985, Avery ran his cousin’s car off to the side of the road. After she pulled over, Avery pointed a gun at her. Avery was upset that she had been spreading rumors about him masturbating on the front lawn, which he stated was not true. Avery maintained that the gun was not loaded and that he was simply trying to stop her from spreading rumors about him. He was sentenced to six years for “endangering safety while evincing a depraved mind” and possession of a firearm.

In July 1985, a woman named Penny Beerntsen was brutally attacked and sexually assaulted while jogging on a Lake Michigan beach. Avery was arrested after the victim picked him from a photo lineup, and later from a live lineup. Although Avery was 40 miles away in Green Bay shortly after the attack – an alibi supported by a time-stamped store receipt and 16 eyewitnesses – he was charged and ultimately convicted of rape and attempted murder, then sentenced to 32 years in prison. Appeals in 1987 and 1996 were denied by higher courts.

Around 1995, a Brown County police detective called the Manitowoc County Jail, saying that an inmate “had admitted committing an assault years ago in Manitowoc County and that someone else was in jail for it”. The jail officer transferred the call to the Manitowoc County detective bureau. Deputies recalled Sheriff Thomas Kocourek telling them, “We already have the right guy. Don’t concern yourself with it.”

Avery’s attorneys also discovered that an evidence box containing a vial of Avery’s blood, collected in 1996 during his appeals efforts in the Beerntsen case, had been unsealed, and a puncture hole was visible in the stopper. They speculated that the blood found in Halbach’s car could have been drawn from the stored vial and planted in the vehicle to incriminate Avery; but FBI technicians tested the blood recovered from Halbach’s car for ethylenediaminetetraacetic acid, a preservative used in blood vials but not present in the human body, and found none. Avery’s defense team presented expert witness testimony stating that it was not possible to tell if the negative result meant that EDTA was not present, or if the test itself was inconclusive.

The second episode of season 18, “Making a rapist”, of the series Law & Order : Special Victims Unit is inspired by the Avery case. Sean Roberts, who was found guilty of rape in 2000, is exonerated by new DNA evidence at the beginning of the episode. But soon, he becomes the suspect in a rape and murder case.

Avery continued to maintain his innocence in the Beerntsen case. In 2002, after serving 18 years (the first six concurrently on the prior endangerment and weapons convictions), the Wisconsin Innocence Project used DNA testing – not available at the time of Avery’s original trial – to exonerate him and to demonstrate that Gregory Allen had in fact committed the crime. Allen, who bore a striking physical resemblance to Avery, had committed an assault in 1983 at the same beach where Beerntsen was later attacked in 1985, and was under police surveillance in 1985 due to his history of criminal behavior against women, but he was never a suspect in the Beerntsen case, and was not included in the photo or live lineups presented to Beerntsen.

Avery was released on September 11, 2003. By that time, his wife had divorced him, and he was estranged from his family.

His wrongful conviction case attracted widespread attention. Rep. Mark Gundrum, Republican chairman of the Wisconsin Assembly Judiciary Committee, impaneled a bipartisan task force to recommend improvements to the state’s criminal justice system aimed at decreasing the likelihood of future wrongful convictions. Recommendations included a revamped eyewitness identification protocol and new guidelines for interrogations of suspects and witnesses, and the collection and storage of material evidence. The recommendations were ultimately drafted into legislation that became known as the Avery Bill, which was passed and signed in October 2005, then renamed the Criminal Justice Reform Bill a month later after Avery was charged in the Halbach case.

Photographer Teresa Halbach disappeared on October 31, 2005; her last alleged appointment was a meeting with Avery, at his home on the grounds of Avery’s Auto Salvage, to photograph his sister’s minivan that he was offering for sale on Autotrader.com. Halbach’s vehicle was found partially concealed in the salvage yard, and bloodstains recovered from its interior matched Avery’s DNA. Investigators later identified charred bone fragments found in a burn pit near Avery’s home as Halbach’s.

Avery was arrested and charged with Halbach’s murder, kidnapping, sexual assault, and mutilation of a corpse on November 11, 2005. He had already been charged with a weapons violation as a convicted felon. Avery maintained that the murder charge was a frameup, promulgated to discredit his pending wrongful-conviction civil case. Manitowoc County claimed to cede control of the murder investigation to the neighboring Calumet County Sheriff’s Department because of Avery’s suit against Manitowoc County, however Manitowoc sheriff’s deputies participated in repeated searches of Avery’s trailer, garage, and property, supervised by Calumet County officers. A Manitowoc deputy found the key to Halbach’s vehicle in Avery’s bedroom. Avery’s attorneys said there was a conflict of interest in their participation and suggested evidence tampering.

Avery filed a civil lawsuit against Manitowoc County, its former sheriff, Thomas Kocourek, and its former district attorney, Denis Vogel, seeking to recover $36 million in damages stemming from his wrongful conviction. The suit was settled in February 2006 for $400,000 following his murder indictment.

In March 2006, Avery’s nephew, Brendan Dassey, was charged as an accessory in the Halbach case after he confessed under interrogation to helping his uncle kill Halbach and dispose of the body. He later recanted his confession, claiming it had been coerced, and refused to testify to his involvement at Avery’s trial. Dassey was convicted of murder, rape, and mutilation of the corpse in a separate trial.

In pre-trial hearings in January 2007, charges of kidnapping and sexual assault were dropped. Avery stood trial in Calumet County in March 2007, with Calumet District Attorney Ken Kratz leading the prosecution, and Manitowoc County Circuit Court Judge Patrick Willis presiding. On March 18, Avery was found guilty of first-degree murder and illegal possession of a firearm, and acquitted on the corpse mutilation charge. He was sentenced to life in prison without possibility of parole on the murder conviction, plus five years on the weapons charge, to run concurrently.

In August 2011, a state appeals court denied Avery’s petition for a new trial, and in 2013, the Wisconsin Supreme Court denied a motion to review the ruling. In January 2016, Chicago attorney Kathleen Zellner, in collaboration with the Midwest Innocence Project, filed a new appeal, citing violations of Avery’s due process rights, and accusing officials of gathering evidence from properties beyond the scope of their search warrant.

After serving five years at the Wisconsin Secure Program Facility in Boscobel, Avery was transferred in 2012 to the Waupun Correctional Institution in Waupun.

On March 26, 2013, the public radio program Radiolab aired an episode titled “Are You Sure?” which featured a 24-minute segment titled “Reasonable Doubt”. It explored the story of Steven Avery from the perspective of Penny Beerntsen, the woman he was wrongfully convicted of sexually assaulting in 1985.

In December 2015, Dassey’s attorneys filed a writ of habeas corpus in federal district court for release or retrial, citing constitutional rights violations due to ineffective assistance of counsel and the coerced confession. In August 2016, Dassey’s conviction was overturned by federal magistrate judge William E. Duffin, who ruled that his confession was involuntary. Duffin granted a defense petition for Dassey’s release on November 14, but an appeals court overturned his ruling on November 17, ordering that Dassey remain incarcerated pending resolution of the state’s appeal of the habeas decision.

On December 20, 2015, a petition was created at a White House petitioning site titled “Investigate and pardon the Averys in Wisconsin and punish the corrupt officials who railroaded these innocent men”. In a January 2016 response to the petition, a White House spokesperson said that since Avery and Dassey “are both state prisoners, the President cannot pardon them. A pardon in this case would need to be issued at the state level by the appropriate authorities.” A spokesman for Wisconsin governor Scott Walker stated that Walker had no plans to consider pardoning Avery.

On December 18, 2015, Netflix released Making a Murderer, a 10-episode original documentary series which explores Avery’s and Dassey’s investigations and trials. The documentary “examines allegations of police and prosecutorial misconduct, evidence tampering and witness coercion.” The series was widely reviewed and discussed in the media. It generated numerous follow-up interviews and articles with parties shown in the documentary, including family members, and some reporters of the trials. A second season of the documentary was released via Netflix on October 19, 2018. In December 2018, Netflix and series producers were sued for defamation by Andrew Colborn, a former police officer for Manitowoc County who testified at Avery’s murder trial. The suit alleges that the series omitted and distorted material in order to portray Colborn as a corrupt officer who planted evidence.

In January 2016, after Making a Murderer had been released on Netflix, People magazine reported that one of the Avery trial jurors was the father of a Manitowoc County Sheriff’s deputy, and another juror’s wife was a clerk with Manitowoc County.

On August 26, 2016, Kathleen Zellner, counsel for Steven Avery, filed a motion for post-conviction scientific testing with the clerk of the circuit court, Manitowoc County, Wisconsin. Judge Angela Sutkiewicz signed a stipulation and order for the scientific testing to proceed on November 23, 2016.

A second petition, titled “Initiate a Federal Investigation of the Sheriff’s Offices of Manitowoc County and Calumet County, Wisconsin”, was submitted to petitions.whitehouse.gov on January 7, 2016. The petition was archived because it did not meet the minimum signature requirements.

In June 2017, the Seventh Circuit upheld the magistrate’s decision to overturn Dassey’s conviction, leaving the state with the options of appealing Duffin’s ruling to the US Supreme Court, dismissing the charges, or retrying him. Subsequently, the state petitioned the appellate court to hear the case en banc. The state’s petition was granted and the appellate court reversed the magistrate’s ruling, finding Dassey’s confession was not in violation of the Constitution. Dassey’s attorneys filed a petition to have the Supreme Court hear his case, but the request was denied. Brendan Dassey remains in prison.

On June 7, 2017, Zellner filed a 1,272-page post-conviction motion citing ineffective assistance of counsel, Brady violations, and affidavits by experts allegedly debunking the manner in which Teresa Halbach was killed, including alleged new evidence and ethical violations by Calumet County D.A. Ken Kratz. Zellner says Steven Avery’s conviction was based on planted evidence and false testimony and is requesting a new trial “in the interests of justice.” On October 3, 2017, Avery’s motion for a new trial was summarily denied without the court holding an evidentiary hearing.

Based on the bone fragments found in the Manitowoc County Gravel Pit, Avery’s post-conviction lawyer now found herself with a new theory and new evidence to be brought into Avery’s upcoming case. This all started in 2018 when Zellner, through Avery, filed a motion to have “suspected human” bones that were being held by the Wisconsin Department of Justice be tested for DNA. The bones to be tested came from three different burn piles within the Manitowoc County owned quarry; amongst them was a pelvic bone fragment. New technology used to identify victims in the California wildfires would allow Zellner, if she had won that appeal, to test the bones to see if they matched the DNA of Teresa Halbach, Avery’s suspected victim. However, when the motion was filed, Zellner soon discovered that the State had returned the bones to Halbach’s family.

On February 26, 2019, the Wisconsin Court of Appeals granted Avery’s petition requesting that his case be remanded back to the trial court for an evidentiary hearing on his motion for a new trial. Kathleen Zellner posted the news to her Twitter page several hours before, tweeting: