Asia Bibi, a farm worker and mother of four, became the first woman to be sentenced to death under Pakistan's controversial blasphemy law in 2010. The Supreme Court will soon begin hearing an appeal against her conviction, said lawyer Saif-ul-Malook. "The execution of Asia Bibi has been suspended and will remain suspended until the decision of this appeal," Malook said. No date had been set for her execution, he added. The prosecution lawyer was not available for comment. The law in predominantly Muslim Pakistan does not define blasphemy but stipulates that the penalty is death. While convictions for blasphemy are fairly common, with most cases involving members of religious minorities, a death sentence has never been carried out. But many people have been killed by angry mobs after being accused of blasphemy. Human rights activists say accusations of blasphemy are sky rocketing because the law is often abused to settle grudges and seize money or property. Attacks on those who have questioned the blasphemy law and called for reform, including the murder of two politicians who tried to intervene on behalf of Bibi, have stifled debate. The governor of Punjab province, Salman Taseer, was shot dead by a bodyguard in 2011 after he had sought a presidential pardon for Bibi. The judge who later sentenced Taseer's killer had to flee the country. Islamist militants claimed responsibility for the murder later in 2011 of the then sole Christian government minister for challenging the blasphemy law. The case against Bibi followed accusations by two sisters who accused her of making derogatory remarks about Islam. Her lawyers say her neighbors had a grudge against Bibi because of an earlier dispute. Malook said key witnesses had not appeared during hearings by the High Court. "The real eyewitnesses ... never appeared before the court and backed out," he said. Evidence in blasphemy trials often cannot be reproduced in court for fear of committing another offence and judges and lawyers often refuse to hear cases because they fear being attacked. Lawyers who here blasphemy cases are frequently threatened. A prominent human rights advocate defending a professor accused of making a blasphemous Facebook post was murdered last year.