In August 1955, Emmett Till of Chicago left his widowed mother to visit his cousins in Money, Mississippi. Fourteen years old, he had never been south before, and Mrs Till, unsure of the wisdom of the trip, urged Emmett, a cocky boy who liked to play the clown, to remember that he could not behave in Mississippi as he did at home. "If you have to get down on your knees and bow when a white person goes past, do it," she said. Putting him in the care of his great-uncle, a preacher, she gave him a signet ring that had belonged to his father, who had been killed in the Second World War. A few weeks later, her son returned in a box. The ring was the only part of him she recognised.
The case became news again this week when it was announced that the United States government is to reopen an investigation into Till's murder. It is also about to feature on the stage again, with a revival of James Baldwin's 1964 play Blues for Mr Charlie, which was based on the murder and subsequent trial.
The town of Money was no more than a dirt crossroads with a few shops and a cotton gin, and although Till enjoyed seeing his cousins, he was soon bored, and bragged of the superior attractions - and freedoms - of Chicago. Up north, he said, black men could talk to white women in public, even take them out on dates. Oh yeah? said a cousin. Let's see you get a date with that white woman, then. The woman referred to, the nearest one at the time of this foolish boast and idle challenge, was Carolyn Bryant, the wife of the owner of the grocery store, who was then out of town.
Accounts differ of what Emmett said and did when he went into the store to buy bubble gum - some witnesses reported that he said nothing, others that he called Mrs Bryant "baby," made a flirtatious remark, and took her hand. All agreed, however, that, on leaving the store, he turned to face her and made an appreciative "wolf whistle". His first realisation of the gravity of his offence was Carolyn Bryant's reaction: she took out a gun.
When her husband, Roy, came home a few days later, she told him what had happened. On the night of 28 August, Roy Bryant and his half-brother J W Milam took their shotguns to the home of Emmett's great-uncle, Moses, and said they wanted Emmett to come with them. A few days later, a fisherman in the Tallahatchie River pulled hard on his snagged line: it had caught on Emmett's body. He had been so badly beaten that his relatives didn't recognise him; one eye had been gouged out, and he had been shot in the head. Local officials planned to bury the body, but Mamie Till insisted not only on its return but on an open-casket funeral, so the world could see what had been done to her boy. The photographs were published worldwide.
At the risk of his own life, Emmett's great-uncle named Bryant and Milam as the men who had taken Emmett away, and they were tried for murder.The two were never put on the stand. The defence, in its summation, told the jury that, if they did not acquit, their ancestors would "turn over in their graves". The reaction of most of America to the verdict was summed up by a headline in an Ohio newspaper: "Mississippi Jungle Law Frees Slayers of Child".
The Till murder was a huge embarrassment to the Eisenhower administration. Its shame deepened when the killers, protected by the double-jeopardy rule, sold to a magazine their story of the murder night and their plea for exculpation. They had only intended, they said, to pistol-whip Emmett a bit, to teach him a lesson. But he kept saying: "I'm not afraid of you. I'm as good as you are." "Well," said Milam, "what else could we do?"
Mamie Till expressed the view of many blacks when she said she had thought that the way blacks were treated had nothing to do with her. "The murder of my son has shown me that what happens to any of us, anywhere in the world, had better be the business of us all." The "sacrificial lamb of the Civil Rights movement", as Emmett was later called, was said to have provided the blood from which the movement sprang. Only two months after the verdict, the campaign of non-violent resistance began when Rosa Parks, ordered by the driver to give up her seat on an Alabama bus to a white man, said no, and sparked the Montgomery bus boycott, led by Martin Luther King.
Baldwin was hardly the only writer to be affected by the case. Gwendolyn Brooks wrote a poem, "A Bronzeville Mother Loiters in Mississippi", in which Carolyn Bryant, watching her husband slap their own child for being naughty, imagines an imprint of blood on its cheek. Bob Dylan wrote, in the ballad "The Death of Emmett Till": "If you can't speak out against this kind of thing, a crime that's so unjust/ Your eyes are filled with dead men's dirt, your mind is filled with dust." The singer Phil Ochs alluded to the murder in his ironically titled "Here's to the State of Mississippi". "If you drag her muddy rivers, nameless bodies you will find/ The calendar is lying when it reads the present time".
The Black Panther activist Eldridge Cleaver, reading about the case in prison, where he was serving time for possession of marijuana, said he suffered a minor nervous breakdown, from which he emerged with the conviction, as he later wrote in Soul on Ice (1968), that, "as a matter of principle, it was of paramount importance for me to have an antagonistic, ruthless attitude toward white women... I became a rapist... Rape was an insurrectionary act, [revenge for] how the white man has used the black woman." Cleaver later made that passage even more inflammatory by saying that, on his release from prison, he practised on black women.
When Susan Brownmiller, who grew up to be a feminist author and activist, heard about the Emmett Till case, her response was a paradigmatic - indeed, self-parodic - one for an educated, middle-class, liberal white girl: she smiled kindly on any black boy or man who whistled at her, eager to show that she believed in equality between the races. But by the time she wrote Against Our Will, a history of rape, in 1975, Brownmiller had arrived at a very different take on the Till case: "Emmett Till and J W Milam shared something in common. They both understood that the whistle... was a deliberate insult just short of physical assault, a last reminder to Carolyn Bryant that this black boy, Till, had in mind to possess her."
The reaction was furious. Brownmiller was denounced by Angela Davis and accused, by the Southern Conference Educational Fund, of having written "a dangerous... book, which... will fan the fires of racism". Later, in her 1999 memoir In Our Time, Brownmiller softened her observation to: "Till and the men who lynched him shared something in common: a perception of the white woman as the white man's property," and dismissed charges that her opinion condoned the murder.
In Blues for Mr Charlie, the mother of the young murder victim tells him: "Hatred is a poison." He answers: "Not for me. I'm going to learn how to drink it - a little every day in the morning, and then a booster shot late at night." To many, Baldwin's rejection of the idea that hatred makes one strong, his plea that "we have the duty to try to understand" the white racist and murderer, will seem dated and weak; to others, it may seem radical. Nearly half a century after a boy's mutilated body was fished from the Tallahatchie, the verdict remains open on his legacy.
'Blues for Mr Charlie', New Wolsey Theatre, Ipswich (01473 295900) 26 May to 5 June; Tricycle Theatre, London NW6 (020-7328 1000) 16 June to 10 July