Dateline NBC

Kathleen and Michael Peterson in happier times.

Michael Peterson, the best-selling author whose 2003 murder conviction in the death of his wife inspired the movie "The Staircase Murders," has been granted a new trial.

Peterson's motion for a new trial was granted Wednesday based on new evidence suggesting that the original investigation was botched and a bizarre alternative theory that has drawn support from scientific experts: the possibility that an owl killed Kathleen Peterson in Durham, N.C., in 2001.

The case had already drawn widespread international attention because of Peterson's fame — his novels "The Immortal Dragon," "A Time of War, A Bitter Peace" and "Charlie Two Shoes and the Marines of Love Company" were well-reviewed and became best-sellers.

Kathleen Peterson, 48, was found dead at the bottom of a staircase at the family's home in Durham. Her husband, now 68, was sentenced to death after his conviction in 2003, but his family has been seeking a new trial based allegations that the State Bureau of Investigation mishandled the case.

Last year, a State Bureau of Investigation agent leading the case was fired after he was found to have mishandled evidence in 34 criminal cases. That was the basis for the ruling Wednesday by Hudson, who set bond at $300,000 and ordered Peterson held under electronic house arrest.

The case has also been closely followed because of an alternative defense explanation that has become known as the Owl Theory.

That evidence included a feather that was found at the scene and affidavits from neuroscientists and veterinary experts — including specialists from the Smithsonian Institution — saying the wounds on Kathleen Peterson's head were consistent with those that would occur if an owl had somehow become entangled in her hair.

In 2007, the case was the subject of "The Staircase Murders," a highly fictionalized account starring Treat Williams. It was also the subject of a 2006 "Dateline NBC" investigation, which raised the question of whether blood splatters at the scene were inconsistent with a blunt-force trauma attack.

Read the full 2006 "Dateline NBC" report

Kathleen Peterson's sister, Candance Zamperini, urged Superior Court Judge Orlando Hudson not to grant Peterson's request for a new trial earlier this month, telling him: "Ten years I've been without my sister. Ten years her daughter hasn't had her. And 10 years the rest of us have been alive and had our freedom, but not Kathleen."

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