The Biggest Michael Peterson Theories: What Really Happened?

On December 9, 2001, Kathleen Peterson was found dead at the bottom of the stairs of the North Carolina mansion she shared with her husband Michael Peterson. The circumstances surrounding her death pointed to different possibilities — some more plausible than others. Michael was charged for the murder of his wife and was found guilty. He was sentenced to life in prison without parole in 2003, but he was granted a new trial in 2011 due to the revelation that a witness gave misleading testimony during the first trial (via Inside the Staircase).

During the second trial, Michael submitted an Alford Plea, which allows a defendant to plead guilty while still maintaining innocence, per U.S. Legal. This may be the best choice for some defendants who know that the prosecution could prove the crime or when the defense lacks evidence to prove innocence. Michael was handed the lesser charge of manslaughter and was sentenced to a maximum of 86 months in prison. However, he was credited for the time he served after his first trial — which was more than 86 months — and he was set free.

The trial was the subject of the documentary series "The Staircase," and the entirety of Michael's case was documented. Although he is now a free man, many people who followed the case have put forward theories on how Kathleen really died.

Kathleen accidentally fell down the stairs

The first theory is Michael Peterson's defense during his trial. Per his account, he and Kathleen drank wine by their swimming pool. After a while, Kathleen decided to go back inside the house while he stayed outside. Michael followed inside the house a while later, and that was when he found Kathleen at the bottom of the stairs, per The Cut. Michael called 911 at about 2:40 a.m. and reported the incident. This theory explains Kathleen's death as a simple fall down a long staircase. Michael presumed that his wife felt the effects of the wine and accidentally tripped.

The problem with the theory, however, is the amount of blood found at the scene. There were blood splatters on the wall of the stairs, and it looked more like a gruesome horror movie than a simple fall. According to Decider, prosecutors also pointed out Kathleen's position on the stairs; her head and upper body were resting on the steps, while her legs were away from the stairs. Furthermore, her autopsy showed lacerations on her head. With these facts laid out, it seems that an accidental fall was highly unlikely, though not impossible.

Kathleen had an undiagnosed illness

Another theory is that Kathleen Peterson suffered from an undiagnosed illness that caused a brain hemorrhage. During the trial, Michael Peterson's past was brought up. Before he was married to Kathleen, he lived in Germany and a close friend — Elizabeth Ratliff — was also found dead at the bottom of a staircase, as reported by Decider. Upon investigation, it was discovered that Ratliff had a brain hemorrhage and accidentally fell down the stairs.

There's a theory that Kathleen suffered a similar fate, and according to some of the couple's children, she didn't go to regular medical check-ups and only went to the doctor when needed. They also said that Kathleen wasn't feeling her usual self before she died. This theory, however, didn't explain the lacerations that were found on her head. The chances of Michael experiencing two similar accidental deaths of the women in his life seem highly unlikely as well.

Michael killed Kathleen

One of the facts that came out during the case was Michael Peterson's scheduled meeting with a male escort months before Kathleen's death. The investigation also revealed that Michael had thousands of photos of nude men on his computer, as well as an email thread between Michael and the said escort, as reported by Esquire. Prosecutors theorized that Kathleen found out about her husband's sexuality, and an argument was what pushed Michael to use a fire poker to murder Kathleen.

Michael didn't deny contacting a male escort, but he said that Kathleen knew about him being bisexual and that they had an open marriage. However, his statement couldn't be confirmed nor denied. If it was true, however, then they wouldn't have had the argument that the prosecution claimed led to Kathleen's death (via Decider). In addition, the fire poker that the prosecution claimed Michael used to attack Kathleen was found untouched and covered in cobwebs at the garage of their home.

An owl attacked Kathleen

Perhaps one of the most controversial theories that came out from the documentary is the one about the owl. During the investigation, a few feathers were found on Kathleen Peterson's hands and hair. These pieces of evidence left some people believing that an owl attacked Kathleen, and the lacerations on her head were caused by its talons. To some, the theory may be absurd, but a specialist says that it is possible.

Kate Davis of the Raptors of the Rockies organization was shown photos of Kathleen's injuries. She concluded that she was, indeed, attacked by an owl based on her wounds and the month of her death — December — which is the mating season for owls and makes them aggressive and territorial (via Audubon). Barred owls were native to the area where the Petersons lived, and other bird experts agreed that it's highly possible that an owl attacked Kathleen and the lacerations were consistent with the shape of its talons. As an expert said, per Cosmopolitan, the wounds are "within the behavioral repertoire of large owls." Although Michael's attorneys believe that it was a possibility, they didn't present the argument in court, as they believed it was too much of a risk.

An owl attacked Kathleen and Michael took the opportunity to kill her

Some believe the possibility that an owl attacked Kathleen Peterson, but Michael Peterson wasn't that innocent either. The theory suggests that Kathleen may have been injured after the owl attack, and Michael may have taken the accident as an opportunity to murder his wife. The presence of feathers and the large amounts of blood may have been caused by such a scenario.

According to Inside the Staircase, Kathleen's wounds on the head are consistent with her head being slammed on a flat object, in this case, a step on the stairs. Other injuries include blunt force trauma to the head, contusions on her hands and arms, and a fracture on the neck cartilage. Michael maintains his innocence amid all the accusations, and it seems that there is no way of knowing what really happened to Kathleen. If Michael is telling the truth, he wouldn't have witnessed what happened on that fateful night. Only Kathleen knew what really occurred, and the pieces of evidence that were left behind tell many different possibilities.