A 37-year-old man yesterday was found not guilty by reason of insanity in the shooting death of a U.S. Park Service ranger on the Big Island in December 1999, federal prosecutors said.

Eugene Frederick Boyce III, who has been hospitalized at various federal prison hospital facilities since the shooting, was turned over to the custody of the federal Bureau of Prisons by federal judge Susan Oki Mollway.

Boyce will be evaluated by mental health experts to determine if he presents a risk of danger to people or property. A hearing is scheduled Nov. 20 on the issue.

Boyce was tried for killing Park Service Ranger Steve Makuakane-Jarrell at Kaloko-Honokohau National Historic Park. The ranger was investigating a visiting woman's complaint about aggressive behavior by Boyce's dogs. During a struggle that ensued, Boyce gained control of the ranger's gun and shot Makuakane-Jarrell twice from close range.

Boyce, who had been declared incompetent to proceed to trial on several occasions, was declared competent last year.

At his trial, the government's psychologist witness, Leanne Preston, as well as defense psychiatrist Pablo Stewart, testified that Boyce suffered from a severe form of paranoia and schizophrenia.

Boyce, who was homeless at the time, believed the ranger was attempting to kill him and his dogs, Preston said.

Ed Kubo, U.S. attorney for Hawai'i, said Boyce has a long history of mental illness and violent acts and "based on this dangerous history, we will aggressively fight to keep (him) in custody, forever, because he poses such a substantial threat to the safety and welfare of our citizens."