UPDATE: The jury found Mitchell not guilty on Wednesday, WRAL-TV reported.

An unusual defense is being put forth in a murder trial out of North Carolina, where a man claims he was sleepwalking when he strangled his four-year-old son.

The jury has begun deliberating in the first-degree murder trial of Joseph Anthony Mitchell, who also faces attempted murder charges for attacking his 13-year-old daughter and 10-year-old son in the Sept. 2010 incident.

Mitchell then barricaded himself in a room inside the home and attempted to kill himself, but police arrived and rescued him. 

His attorneys argued at the trial that Mitchell had no motive to kill his children and that prosecutors have not proven beyond a reasonable doubt that Mitchell intended to harm his kids.

The prosecution  argued that Mitchell snapped amid financial trouble, marital problems and his continuing unemployment.

WRAL reported:

Dr. George Corvin, a forensic psychiatrist who testified for the defense, said last week that Mitchell was likely suffering from "non-REM parasomnia," a sleep disorder where he could perform random acts unconsciously and could become violent if triggered by a loud noise.

Mitchell testified that he was in financial distress, having been unemployed for two years and trying to secretly rescue his home from foreclosure, and had gotten little sleep in the weeks leading up to Blake's death.

Corvin said stress and a lack of sleep likely led to the parasomnia, and he said Mitchell was incapable of exercising any criminal intent in carrying out the attacks.

Nancy Laney, a psychologist at Central Regional Hospital in Butner who interviewed Mitchell four times over the past year, disputed that claim on Monday, saying she found no evidence that Mitchell suffered from any mental condition that would have left him unconscious at the time of the attacks. She argued that he consciously planned and carried out the crime.

Jon Scott discussed the case this afternoon on "Happening Now," asking two legal experts whether this defense will work.

Defense attorney Rebecca LeGrand called it a "longshot" strategy that has rarely worked in other instances.

LeGrand added that the jury would need to be convinced that Mitchell did not know what he was doing. 

Attorney Heather Hansen said it's become harder for defense attorneys to prevail with this strategy ever since the acquittal of John W. Hinckley, Jr, who was found not guilty by reason of insanity in the 1981 shooting of President Reagan.

"Not only did the law change with regard to these types of defenses but juries' aversion to these defenses grew," she said. 

Watch the discussion above.