Did Steven Avery Do It? 5 Theories About Who Killed Teresa Halbach

From Teresa's ex-boyfriend to members Avery's own family, here are five alternate theories about who killed Teresa Halbach.

Last month, much hype surrounded the release of Netflix’s Making A Murderer docu-series, which examined the case of Steven Avery, a Wisconsin man who spent 18 years in prison for rape before being exonerated by DNA evidence—and then, two years later, found himself back behind bars for an even worse crime: the 2005 death of 25-year-old Teresa Halbach. His teenage nephew, Brendan Dassey, was also convicted for her death in a separate trial.

Avery has maintained his innocence throughout—as has Dassey, after recanting an earlier confession that led to the charges—and the defense posited at trial that Manitowoc County officers had framed Avery for the crime by planting evidence. Ten years in the making, Netflix’s 10-episode series delves into Avery’s long history with the Manitowoc County Sheriff’s Department, providing further context for his framing defense through original interviews with Avery’s family and attorneys, and examines the police investigation and chain of events that led to Avery and Dassey’s convictions.

Teresa Halbach

Avery’s most prominent detractors—like Prosecutor Ken Kranz, and the long list of Wisconsin police officers involved in the investigation—declined to participate in the series and are thus seen mostly through courtroom footage and media interviews. Alternately, Avery’s biggest supporters—including his parents and his two impassioned attorneys, Dean Strang and Jerry Buting—did cooperate with filmmakers, resulting in a documentary series that some claim is skewed in favor of Avery’s innocence.

It’s certainly true that, despite the series’ length, Making A Murderer does not cover everything about the Steven Avery case, though the filmmakers insist that they included the State’s most damning evidence of Avery’s guilt in the documentary. Many of these overlooked or downplayed bits of evidence—like Avery’s prior history of violence against women and animals; his alleged “strange” behavior during prior meetings with Halbach; the State’s contention that the shell casing found in Avery’s garage not only had Halbach’s DNA on it, but also matched a rifle that hung over Avery’s bed—warrant another look at the case.

Dean Strang (left) and Jerry Buting (right)

There are many who believe Avery is guilty as charged and convicted. But naturally, Making A Murderer’s calling that into question has sparked the Internet’s armchair detectives to theorize about what really happened to Teresa Halbach. Here are the most common theories floating around and the supporting evidence—or lack thereof.

Theory #1: Scott Tadych (Avery’s brother-in-law) and Bobby Dassey (Avery’s nephew and Brendan Dassey’s brother) killed Halbach (purposefully or accidentally) and framed Avery for the crime … and then sat back and watched as the Manitowoc County Sheriff’s Department separately did the same.

Evidence: The amount of evidence found on the Avery property—including Halbach’s remains and her car—has led many to surmise that if Steven Avery and Bobby Dassey are innocent, the real killer would still likely be someone who had similar access and opportunity, both to Halbach herself and the Avery property. A number of other Avery family members also lived on the property at the time, including Tadych, Janda and all four of the Dassey boys. It was Janda’s car that Halbach came to photograph for Auto Trader magazine, and Tadych more than likely was privy to her visit. Bobby Dassey testified to seeing Halbach taking pictures of his mother’s car, and both men had access to the various locations where evidence was found. Neither was fingerprinted or submitted DNA, and the trailer where they lived was not searched, so there’s no way of knowing if there was evidence linking them to Halbach’s murder, because they were not investigated.

Other Evidence: Bobby is believed to be Tadych’s accomplice in this theory, based on the fact that the pair conveniently alibi each other for the time of the murder. Both claimed to have gone hunting that afternoon/evening, but not together, and said they passed each other on the highway during the window of time Halbach is believed to have been killed—but there are no other witnesses to offer further corroboration.

Tadych, meanwhile, has a long history of being violent towards women, and showed a strange level of enthusiasm for his brother-in-law’s conviction (he called it “the best thing in the world ever”) despite knowing his son-in-law, Brendan, was facing similar charges. Meanwhile, Bobby Dassey’s testimony at trial had notable inconsistencies and misleading statements, and an unrelated examination the same week as the murder reportedly revealed that Bobby had scratches on his back. Additionally, shortly after Halbach’s death, a coworker of Tadych’s claimed that he was trying to sell a .22 rifle, the same as the gun believed to be the murder weapon, which he said belonged “to one of the Dassey boys.”

Sources: Court Document; Fusion; Reddit; Reddit

Theory #2: Chuck and Earl Avery killed Halbach and framed their brother.

According to TMZ, Steven Avery filed legal documents in 2009 which pointed the finger at his brothers, saying there had been a fight over the family business and that the pair was jealous of the multi-million dollar settlement he was expected to get from his civil case. The defense also had the Avery brothers on their list of possible alternate suspects.

Potential Evidence: Like Tadych and Dassey, both Chuck and Earl lived and worked on the Avery property and had access to all the same locations where evidence was found. Both have disturbing criminal histories, including allegations of rape, child molestation and violence against women.

The day that Halbach’s car was found “hidden” in the Averys’ salvage yard, Earl was working and allowed volunteers to search the lot for Halbach’s car–which they found in less 30 minutes. According to the documents filed by Steve Avery, Charles Avery had allegedly harassed at least three women who visited the junk yard within a month of Halbach’s death.

Sources: TMZ; Court Documents

Theory #3: Officers from the Manitowoc County Sheriff’s Department—specifically Sergeants Lenk and Colborn—did not kill Halbach, but planted evidence that implicated Avery. Avery’s defense team suggested that the officers believed Avery was guilty of the crime and only planted evidence to secure a conviction, ignoring other potential suspects. However, Internet theorists are less generous about the officers’ motives, with many suggesting that the police didn’t care about who killed Halbach, but wanted Avery to take the fall because his multi-million dollar civil suit settlement was going to bankrupt the county and humiliate many members in local law enforcement.

Sergeant Andrew Colborn and Lieutenant James Lenk

Evidence: Avery’s lawyers, Dean Strang and Jerry Buting, pointed to Lenk and Colborn’s continued involvement in the investigation even after the Manitowoc County Sheriff’s Department was taken off the case. In fact, Lenk and Colborn were present for or linked to discovery of a couple key pieces of physical evidence, including the key to Halbach’s RAV-4, which was suddenly found in Avery’s trailer after it had already been searched multiple times to no avail. Not to mention, on the same day that Halbach was reported missing, Colborn called in a license plate number that matched Halbach’s plates. Two days later, her car was found by a couple of volunteer searchers, only the plates had been removed and tossed into another nearby vehicle.

Some supporters of this theory have suggested that Colborn might have been searching the Avery property without a warrant, found the car and knew he couldn’t call it in; others think he found the car and Halbach’s body in an entirely different location, burned her body and then planted her remains and the car on the Avery property, removing the plates and stashing them elsewhere to increase the chances of them being found.

If they did indeed have access to the RAV-4 before it was officially discovered, Lenk and Colborn could have planted additional evidence, theorists say, including (as the defense posited at trial) Avery’s blood, a vial of which was stored at the city clerk’s office. Lenk was one of the few people who knew about the blood vial and would have had access to it, and both the box the vial was stored in and the vial itself appeared to have been tampered with. (Ultimately, the State had the FBI created a test which their expert witness claimed proved the blood in Halbach’s car couldn’t have come from the vial, but the defense’s witness disagreed that such a conclusive result could be reached.)

Sources: Reddit

Theory #4: Ryan Hillegas, Teresa’s ex-boyfriend, killed her.

Motive: Usually when a person, especially a woman, is murdered, investigators put boyfriends and ex-boyfriends at the top of their list of potential suspects, as intimate partner violence is exceedingly common. Yet Hillegas was never treated as a suspect by investigators.

Evidence: Uncorroborated allegations that Hillegas has a history of stalking have circulated on the internet, as have photos taken the week of Halbach’s disappearance which reportedly show Hillegas had deep scratches on his hands. But his cold reaction and strange behavior after Halbach’s disappearance are at the center of this theory.

Hillegas testified that after Halbach went missing, he hacked into her voicemail and successfully guessed her password so he could listen to her messages, which strikes some as suspicious and unlikely. A cell phone expert testified that though Halbach’s voicemail filled up in the days after her death, some messages had been deleted – messages that believers of this theory say probably were from Hillegas, and he deleted them because they made him look guilty. Of course, if Hillegas did kill Halbach then he still would have had to have at least planted the car and her remains back on the Avery property, though most of those who suspect Hillegas is guilty still think the police planted additional evidence, like Halbach’s car key and Avery’s blood.

Sources: Reddit; Reddit

Theory #5: Steven Avery did it, with or without the help of Brendan Dassey.

Evidence: There are those who believe that Steven Avery is responsible for the murder of Teresa Halbach. As we mentioned previously, there was evidence that was not presented in the “Making A Murderer” series. Armchair detective Dustin Rowles lays out the alleged omitted evidence here. Despite the alleged omitted evidence, the prevailing feeling online is that due to cognitive disabilities and coerced confessions, Dassey is an innocent victim.