At 10.55am on 27 November 1978, San Francisco City Supervisor Dan White shot and killed Mayor George Moscone with four bullets. He reloaded, ran through City Hall and killed Supervisor Harvey Milk with another four. At his trial, a psychiatrist for the defence argued that White's consumption of junk food led to vacillations in his blood-sugar level and exacerbated indications of manic depression. Instead of going down for murder, he walked away with a seven-year sentence for voluntary manslaughter.
In a surprising instance of self-control, the lawyers in the OJ Simpson trial didn't try the junk food defence. Nor did they say the plaintiff had been influenced by watching too many musicals, but one peek at the 1975 show Chicago would have revealed an extraordinary case of life imitating art.
Ladies and gentlemen of the jury, consider the facts laid before you in this musical. A woman shoots her lover and tries to pin the blame on someone else. It doesn't wash and she's banged up on murderer's row. She hires the flashiest lawyer in town who whips up a storm of publicity and turns the trial into a media circus. She becomes a national celebrity, the nation holds its breath: she gets off. I rest my case.
This collision between fact and fiction actually dates back to 1927, when Maurine Watkins turned a real-life story into a play and then a film called Chicago. Fifteen years later, Ginger Rogers played the title role in Roxie Hart, a tart, brittle, very funny screen version of the crime. Broadway star Gwen Verdon tried and failed to get the rights for years, but Watkins finally relented and left the property to her in her will. Verdon took the project to director and choreographer Bob Fosse who teamed up with lyricist Fred Ebb and composer John Kander and the musical opened on Broadway in June 1975.
Three weeks later, A Chorus Line opened and everyone forgot Fosse's show. It ran for two years, but beneath the glamorous surface of this shimmering show, there's a jet black cynicism about American values and the judicial system which didn't endear it to the nation. One of its greatest strengths is that never for a moment does it soften up or go sentimental.
Two decades later, in the wake of OJ, you can't get a seat for the sensational New York revival: a musical has taken the pulse of the nation. Last I heard, the London production has clocked up a staggering advance in excess of pounds 2.5m, and it's still only in preview. Walk past the theatre and you'll see the happy sign announcing "House Full". If the legal hoop-la surrounding the Louise Woodward trial is anything to go by, I think we can assume that a peculiarly high percentage of the audience on both sides of the Atlantic have been lawyers.
Adelphi Theatre, London W1 (0171-344 0055)