LIHU'E, Kaua'i — A Waimea taro farmer has been acquitted of first-degree murder after a Kaua'i judge ruled he was suffering from a mental disorder when he killed his landlord last year.

Raymond Ard, 41, has been in custody since his arrest the day after the Feb. 27, 2005, attack. He was charged with repeatedly stabbing retired physician Dr. Jon Kerns, 64, and of attempting to murder his own 15-year-old disabled stepson, Richard "Kai" Iwatate.

Family members and neighbors told police that Ard was behaving strangely for several days before the attack, according to court documents. Ard told police that God had spoken to him, telling him that Kerns was "Satan in the flesh."

A nonjury trial was held May 8, with 5th Circuit Judge Kathleen Watanabe entering her findings and verdict Thursday. The judge found that although Ard intentionally caused Kerns' death and intended to kill Iwatate, he was suffering from a mental disorder that substantially impaired his ability to appreciate the wrongfulness of his conduct or to follow the law.

After concluding that Ard presented a risk of danger to himself and others, Watanabe committed him to the custody of the Department of Health to be placed in an appropriate institution for care and treatment.

Kerns, who retired in 2002 from a California medical practice, had invited Ard, his wife and his stepson to stay at a cottage on his Waimea Valley property after learning the family was homeless. The night of the stabbing, Ard ate dinner with Kerns and his wife, Claudia, who later told police Ard had made references to figures in the room who weren't really there.

Ard persuaded the Kerns to come into the cottage, and a short while later, Claudia Kerns heard her husband yelling and from her home could see Ard repeatedly striking Kerns.

He suffered a slashing wound to his neck, deep stab wounds to his chest and numerous other knife wounds.