From his home in northwest Houston, he mails out his eight-page newsletter titled "The War Is Now!" He has 600 subscribers worldwide. He's also written the self-published books Is the Pope Catholic? and The Enemy Is Here, which features a cover with a map of Italy and an arrow pointing to Rome.
He's gained international notice in some segments of the theological community from his years spent denouncing the pope as an impostor.
"Whenever you say 'plot,' people automatically think 'nutcase,'" Gibson explains. "But there's no way this could happen by accident. There's no way this was not rigged."
But Gibson gets recognition far beyond his scholarly arguments about Catholic conspiracy theories. He also happens to be Mel's old man--he's the father of one of the most established superstars in Hollywood, and he lives in the Houston area.
The elder Gibson doesn't believe the Holocaust happened and thinks the idea of evolution is ridiculous. He likes detective novels. The 84-year-old closes his blue eyes when he talks, often slipping into Latin. Instead of saying hello or using any other greeting when he answers the phone, he just says the last four digits of the number in a brisk military tone.
The missal Gibson uses is in Latin. The prayer book's battered spine is covered in masking tape; his 11 children have torn out hunks of its pages.
While he avidly tells of his crusade against the Catholic leadership, Gibson refuses to talk about his family or his famous son. Mel reportedly was outraged when The New York Times Magazine recently interviewed his father; the New York Post reported that Mel Gibson declared the Times story a "hit piece" on him and that the newspaper had harassed his father. The Times story quoted the elder Gibson calling the pope a "Koran kisser" and implied that he sounds a bit like the obsessive-compulsive, newsletter-writing, Catcher in the Rye-collecting character Mel played in Conspiracy Theory.
The elder Gibson's unique life would seem suited for big-screen treatment itself.
His mother, an opera singer, died in New York City before he was 2. She had slipped in the shower and injured her neck. "It was a rather large neck," Gibson says. Gibson's father manufactured brass plumbing supplies until he went out of business in 1928. He died almost 10 years later.
Gibson was third-best academically in his high school class, graduating when he was only 15. "Nobody's ever going to get me into a classroom again," he says.
Gibson studied for the priesthood at a mission 20 minutes outside Chicago. He intended to become a missionary, but he balked at the idea of being sent to New Guinea or the Philippines. "I just lost it," he says. "I did not want to go."
He went after lots of other work. Gibson delivered telegrams for Western Union, planted trees for the Civilian Conservation Corps and built houses for the forestry department. During World War II, he was a first lieutenant in the Army Infantry and Signal Corps based in New Caledonia and Guadalcanal.
Gibson married after his military discharge. The couple planned to have 12 kids and a Saint Bernard. "We never made it," he says. They had only 11 kids. "We did get the dog." But the dog was run over two weeks later. He told his kids that he wanted 100 grandchildren. Thus far, he's the grandfather of 48 and has 15 great-grandchildren. He doesn't buy any of them Christmas presents.
He worked on the railroad as a brakeman for 24 years, until he slipped off a steel platform covered in oil and snow. He was forced to retire because of the injuries.
The sixth of the Gibson children, Mel, described his dad in a Playboy interview as "just a regular guy who worked long hours, supported a big family and kept us all in shoes and food...He's a bookish guy. Uses words I've never heard of."
In 1968, Hutton Gibson took his disability money and cash he had won on Jeopardy! and moved to his mother's native Australia. He didn't want his eldest son drafted in the United States.
"They had a draft in Australia, too, but they were a little more humane," Gibson says. "He couldn't see from here to the wall, but they would have taken him anyway. So I figured, why should he go? I saw what happened to my war--they just gave it away."