Steven Avery has a criminal history that spans more than three decades. However, he insists he was wrongly convicted of at least two of those crimes — which include the murder of 25-year-old Teresa Halbach. A Netflix documentary series, titled Making a Murderer, appears to confirm Avery’s innocence. Although the documentary sparked heated controversy over the murder conviction, authorities contend key evidence was blatantly missing from the series.

Badger Diggings reports Steven Avery was convicted of his first crime in 1981. At the age of 18, he was arrested and charged with burglary after breaking into a local bar. As he pleaded guilty, he was sentenced to 10 months in jail.

Within months of his release, Avery was arrested and charged with animal cruelty. According to reports, he and a close friend “poured gas and oil” on his pet cat and proceeded to toss “it in a bonfire… ” Steven pleaded guilty to the heinous crime and was sent back to jail in 1983.

200,000+ sign petitions calling for pardon of ‘Making a Murderer’ subject Steven Avery. https://t.co/FEEt1uPfRr pic.twitter.com/DLP2Qsch4T — NBC Nightly News (@NBCNightlyNews) January 4, 2016

Two years later, he was convicted of deliberately crashing into his cousin’s car and threatening her with a gun. At the same time, he was charged in the rape of Penny Beernsten.

Although Steven pleaded guilty to assaulting his cousin, he vehemently denied raping Penny Beernsten. Despite his protests, he was ultimately convicted of attempted first-degree murder, false imprisonment, and first-degree sexual assault. He was sentenced to 32 years in prison.

In 2002, the Wisconsin Innocence Project launched their own investigation into Penny’s rape. As a result of their investigation, the state crime lab was ordered to reexamine evidence collected at the scene.

The lab subsequently collected DNA from 13 hairs, which were recovered from Beernsten’s body. However, they concluded that none of their hairs belonged to Steven Avery. Instead, one of the hairs matched the DNA of Avery’s nephew — who was serving time for the rape of another woman.

After spending 18 years in prison, Steven’s sentence was overturned. Post-Crescent reports he was released from custody on September 11, 2003. Two years later, he was named a primary suspect in the disappearance and death of 25-year-old Teresa Halbach.

On October 31, 2005, Teresa had an appointment to take photos of vehicles at Avery Auto Salvage for Auto Trader Magazine. She was never seen or heard from again.

Five days later, authorities discovered the young woman’s vehicle in the Avery Auto Salvage parking lot. They also discovered “bone fragments, teeth… camera and cellphone pieces… in a burn pit near [Steven] Avery’s trailer” and a bullet from Avery’s gun — which was covered in the victim’s blood. Authorities later determined blood found inside Halbach’s vehicle belonged to Steven.

The Independent reports the most damning evidence may have come from Steven’s 16-year-old nephew, who admitted “he and his uncle had kidnapped [the victim] and raped, stabbed, and shot her.”

On November 15, 2005, Steven Avery was charged with first-degree intentional homicide, mutilation of a corpse, and possession of a deadly weapon. Prosecutors later added charges of false imprisonment, kidnapping, and sexual assault. However, the kidnapping and sexual assault charges were later dismissed.

Avery contends authorities conspired to frame him for Teresa Halbach’s death and planted evidence to secure the conviction — in retaliation for a lawsuit he filed for the prior wrongful conviction.

In 2007, Steven was convicted of first-degree intentional homicide, mutilation of a corpse, and possession of a firearm. He was subsequently sentenced to life in prison without the possibility of parole.

Eight years later, a Netflix documentary series, titled Making a Murderer, raised serious questions about Steven Avery’s arrest and conviction.

The documentary explores the possibility that authorities did, in fact, plant evidence at Avery Auto Salvage in an attempt to secure a conviction.

Although the documentary series convinced hundreds of thousands of viewers to sign a petition to overturn Steven’s conviction, former Calumet County District Attorney Ken Kratz said “80 to 90 percent of the physical evidence, the forensic evidence, that ties Steven Avery to this murder” was never mentioned in the series.

According to Kratz, Teresa Halbach took photos at Avery Auto Salvage for Auto Trader on several occasions. Ken said the young women expressed that she was “creeped out” by Steven and his behavior when she was called to take photos at the salvage yard.

Kratz also said Steven Avery called Teresa’s cell phone several times on the day of her disappearance. However, he used software to cloak his number each time he called.

[Image via TribZap]