A state judge Friday found Wai­anae pig farmer Clayton Higa not guilty by reason of insanity in the 2006 bludgeoning death of his girlfriend, committing him to the Hawaii State Hospital.

Higa, 46, fatally beat 21-year-old Shantel Figue­roa with a hammer Feb. 4, 2006, at his farm after he tried to shoot her but his rifle misfired.

He believed Figue­roa was cheating on him, and just before the killing, the two had argued at Figue­roa’s aunt’s house. After he bludgeoned Figue­roa, Higa called the aunt to tell her what he did before stabbing himself in the abdomen with a knife.

It took years for Higa’s case to go to trial because of questions over his mental fitness.

A panel of mental health experts was appointed by the court three times, and each time the experts were split in their opinions, with one finding Higa mentally fit and two finding him not mentally fit.

The three experts on a fourth panel the court appointed to determine whether Higa had the ability to distinguish right from wrong and to follow the law at the time he killed Figue­roa also were split in their opinions, with one expert finding him criminally responsible and two finding him not responsible.

On Friday, following a brief nonjury trial, Circuit Judge Michael Wilson found that Higa was suffering from a mental disease, defect or disorder when he killed Figue­roa, and acquitted him of murder. Wilson noted that the mental health experts had determined that Higa was mildly mentally retarded and had been suffering from long-term brain damage and seizures.

Wilson also found Higa a danger to himself and others and committed him to the Hawaii State Hospital.