Durham dad goes to trial for 4-year-old son's death

Mitchell, who faces one charge of first-degree murder and two charges of attempted first-degree murder, has pleaded not guilty, and defense attorney Jay Ferguson plans to claim that he was not aware of or culpable for his actions.

The defense, called "automatism," is sometimes referred to as a "sleepwalking defense," where defendants argue they are not guilty of a crime because they were sleepwalking and were not aware they had done anything wrong.

Blake Mitchell was suffocated on Sept. 22, 2010, in the family's Durham home, at 17 Thistle Trace.

Joseph Mitchell's 10-year-old son and 13-year-old daughter told investigators that they awoke to find their father trying to cover their mouths or faces, and they had to fend him off, according to court documents.

Joseph Mitchell was found with stab wounds and cuts that authorities said were self-inflicted.

Investigators have said the Mitchell family had suffered numerous financial setbacks, and their foreclosed home was close to being turned over to a bank at the time of Blake Mitchell's death.

They also obtained evidence that Joseph Mitchell had had at least one affair, according to court documents.