The problem with making a documentary about Muhammad Ali — the most celebrated sports figure of all-time — is that every facet of his extraordinary life had already been analysed and dissected in microscopic detail.From the superb 1996 Oscar-winning documentary ‘When We Were Kings’ — about Ali’s Rumble in the Jungle with George Foreman, to the Oscar-winning film ‘Ali’, starring Will Smith, there seems very little left to tell about the self-proclaimed greatest boxer of all-time.Filmmaker Bill Seigal’s ‘The Trials of Muhammad Ali’, though, skilfully chooses to focus on the Ali’s life outside the ring, primarily his involvement with the Black Muslim movement and his refused induction to the army at the height of the Vietnam War.Underpinning Seigal’s documentary is the often forgettable fact that Ali was once reviled as he was revered: a figure of hate for many Americans, struggling to come to terms with race relations, who considered him a conscientious objector.That Ali didn’t have “no problem with them Vietcong” saw the reigning heavyweight champion of the world banned from boxing for three years and facing five years in prison while the courts decided what to do with him.Although told in a linear fashion, it’s far more than just a paint-by-numbers documentary, helped by the rare interview footage Seigal has managed to unearth of the ever-watchable Ali, on talk shows and at college campuses, defending stance on Vietnam.Ali eventually prevailed in his own personal war with arguably his most formidable opponent, the US Supreme Court, returning to the ring to win over the hearts and minds of the American people whose views on race and religion he helped change during those exile years.‘The Trials of Muhammad Ali’ will be shown at BUEI, as part of Bermuda Docs festival, on Saturday at 8.30pm.