Five brides for five brothers can mean a death sentence in Pakistan, writes Graham Usher in Mianwali They live in a kind of exile -- three sisters, three brothers, a mother and a father in a "safe" house in Khushab in Pakistan's northern Punjab. Even within the home there is a sense of sequestration. As a male journalist I cannot speak to women directly -- a female colleague must do the interview for me. But I can hear the women's voices. They are compelling. "Vani is tyranny," says Amna, one of the sisters. "If we were to marry those boys, it would be the same as murder. I know by talking to you we have taken a risk. But as long as we don't act, the government will not act. For us it's a kind of jihad." Amna, Abda and Sajida Khan are "vani" brides. Vani is a centuries-old tribal custom in Pakistan in which girls are given in marriage to settle a blood-feud between two families. There is no pretence that vani is anything other than punishment, says Zia-ullah Khan, a local community activist. "At a vani wedding, there are no drumbeats, no dances and no henna. There is a funeral dirge -- for the bride is about to suffer death. She will be abused, humiliated and generally treated as a slave. Her parents will pray for her death, not only because the vani, the stigma, ends with her life, but also to spare her." No one knows how widespread vani is in Pakistan. In the Mianwali area, near Khushab, Zia-ullah says there are 20-30 vani cases in a community of 30,000. But "there could be many, many more". For the last six years he and others have been campaigning against vani. In January this year the government declared the practice illegal. But the law is flouted by powerful coalitions of tradition, patriarchy and a local police force that "does not quite approve of women's emancipation". It is rare for vani victims themselves to speak out. Which is why the sisters are so important, says Zia-ullah. "If they succeed, hundreds will follow." The sisters' trial began in 1991 -- when Amna was six, Abda four and Sajida one. Their uncle, Mohamed Iqbal, shot dead a cousin in their home village of Sultanwala. A local court convicted Mohamed of murder and sentenced him to death. For the next four years he lived as a "fugitive", he says. In 1995, he was summoned to the village jirga -- a council of elders made up of local politicians, landowners and religious leaders, all very much under the sway of the larger, "aggrieved" family. Cradling the gun he used to kill the cousin, Mohamed recalls the verdict. "I was told that to be pardoned for the murder I must surrender my daughter to marriage, my brother's daughter to marriage and my other brother's three daughters to marriage. I agreed out of fear." The sisters' father, Jehan Khan Niazi, was also at the jirga. "We were given five minutes to decide and at the point of a gun. So I gave my daughters in vani. Maybe I was a coward but I felt the situation was dangerous." Amna cannot remember the verdict. "All I remember is that my mother cried a lot," she says. But the father did take action to redress "the bloody tradition". He had already moved his family to Khushab, 80 kilometres from Sultanwala. He did this not only for security but also to give his daughters an education. "There is one girls' school in Sultanwala," he says. "And that is used for cattle." The investment paid off. Today Sajida is in her final year at school, Abda is at a pre- medical college and Amna is taking a Masters Degree in English. All three take sustenance from their father's support. He takes strength from them. "It was the girls who resisted vani, not me. I am simply their spokesman," he says. Last year the aggrieved family made it clear that unless the girls were given as brides the vendetta would be renewed. Mohamed Aslan Khan is the uncle of the murdered cousin. He lives less than 400 metres from the home of Mohamed Iqbal, the murderer. Crowned with a shock of white hair, he has the demeanour and much of the ruthlessness of your classical tribal patriarch. He explains what for him, and his family, is the unassailable logic of their case. "We are kin and they betrayed us. They affronted our honour. According to our Pathan culture the girls are already our daughters-in- law. In any case, the law against vani was passed in 2005. The marriage was agreed in 1995." As presently drafted it is unclear whether the law is retroactive. In any case, says Zia-ullah, it is unenforceable, because it metes out the same punishment to the givers of vani brides as to the takers. "It won't work," he says. "No woman in the Punjab will go to court to have their parents arrested." The sisters are not taking their case to court. They are appealing to Pakistan's Supreme Court and President Pervez Musharraf, and are doing so through the press. It has proved successful. Editorials have been written in their favour, the BBC's Urdu service is running a series of programmes on vani and women and human rights organisations are campaigning vigorously on their behalf. But the risks are enormous. Last month two of the girls' cousins were shot and wounded while ploughing their fields in Sultanwala. When Amna goes to university, she is chaperoned by her brother, who sleeps with a machine gun by his bed. Her father has offered to leave his job and sell his property in compensation to the aggrieved family. To no avail: "if the girls refuse the marriage, enmity between the two families will continue and 200 will die," says Mohamed Aslan Khan. "Peace depends on them." This is why the case of the "three sisters" is making waves. It pits against the other two parallel systems of authority -- one based on tribe, tradition and honour, the other on justice, law and rights.