Guitar great and Fleetwood Mac founder Peter Green was not a man without troubles, and on Jan. 26, 1977, his struggles landed him in prison and committed to a mental hospital.

Like the blues artists he loved, Green had his share of despair. He was a somewhat fragile soul, and substance abuse didn't help matters. He and his bandmates were turned onto LSD, Green's drug of his choice, by infamous Grateful Dead comrade Owsley Stanley while playing a date in San Francisco. The band was initially hesitant, but eventually dove in head first – and no one more than Green.

He found acid, then found God. Things came to a head while Fleetwood Mac was on tour to promote their third album, Then Play On. "Peter took some more drugs," Mick Fleetwood later said in the BBC documentary Man of the World, "and never really came back from that."

Green was met by a group of people Fleetwood referred to as "the German Jet Set," who whisked him away to a party following their show. "It was a hippie commune sort of thing," Fleetwood Mac guitarist Jeremy Spencer said. "We arrived there, and [road manager] Dennis Keane comes up to me shaking and says, 'It's so weird, don't go down there. Pete is weirding out big time and the vibes are just horrible.'"

Green was already set to leave the band but this was "the final nail in the coffin," as Fleetwood put it. Friends say Green was never the same after the Munich incident. He left Fleetwood Mac in 1970 and stepped out of the spotlight, but his behavior grew even more erratic while his drug use continued.

After a particularly explosive acid trip, Peter said he "started acting strange ... strange things started happening." His brother Len added, "he was hearing voices telling him to do nasty things." He began giving his guitars and his money away, and took on a series of odd jobs, including gravedigger. During these years, he spent time in various psychiatric hospitals, at times undergoing electro-shock therapy.

By the mid-'70s, as Fleetwood Mac entered a new, very prosperous era. New fans began to dig through older Fleetwood Mac recordings, and the royalty checks really began to roll in. Green wanted no part of his past, including the money, while trying to lead his new simple life. Frustrated, Green contacted a former Fleetwood Mac manager about his financials. "I phoned up and asked him if he had any money," said Green in Man of the World, "and he said, 'The accountant's got your money.'"

So on Jan. 26, 1977, Green armed himself with a shotgun he smuggled in from a trip to Canada and paid accountant David Simmons a visit, threatening to shoot him. The twist is that Green was not upset about lack of money, but rather was distraught because the royalty checks kept coming.

The police were called and Green was arrested and thrown in jail. "I was quite happy in prison, so I thought I'd be alright," Green saidm "but they said, 'You failed the psychiatrist test.'"

Green was committed to a mental institution and placed under heavy sedation. He was eventually diagnosed with schizophrenia. After a period of time was released to live with his family, however, when the doctors said the environment of the hospital was more detrimental than it was helpful.

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