A CRUCIAL decision in Portugal this week on the fate of a Hong Kong man facing extradition to China from Macau will set an unbreakable precedent for others in his predicament, a human rights lawyer has claimed. Yeung Yuk-yeung, 36, was arrested in Macau in December 1993 on charges of strangling a woman in a mainland hotel. Since his arrest, China has been lobbying for his extradition. If found guilty of murder in China, Yeung would face the death penalty. But under existing legislation China has no extradition treaty with Macau. Yeung's lawyer Pedro Redinha said the results of an appeal to the plenary sitting of the Constitutional Court of 13 judges in Lisbon would be known on Thursday morning. The appeal was made to prevent Yeung being deported. If the decision goes against Yeung, Mr Redinha said he was prepared to take the case to the European Commission of Human Rights and had already supplied the commission with details. 'If the Constitutional Court rejects Mr Yeung's case then I will pursue this through the commission,' he said. 'To extradite my client to China where he would almost certainly be executed is a violation of the European Convention on Human Rights to which Portugal is a signatory.' Mr Redinha said a decision not to deport was crucial for the future of Macau and the system of justice which followed after the handover to China in 1999. 'If there are others facing extradition then the decision on Thursday of the court in Lisbon is the one that must apply. 'In every such incidence, the same 13 judges will make the decision on whether or not to extradite and if it is made on the basis of sending someone to their death then the same decision must be made every time. This decision should be unbreakable.' He said Yeung claimed he had not killed anybody and that at the time he is said to have murdered the woman, he was on a train in Guangdong. 'The difficulty we have is that Chinese authorities will not give us exact details of the murder including the exact time when it was supposed to have taken place, so it is very difficult to make a case.' Macau's Amnesty International representative Isabel Maria de Costa Morais said Yeung's case was a typical example of the difficulties encompassing the legal systems of Macau, Portugal and China. 'This man faces death for something we have been told very little about yet China expects us in Macau to extradite him. 'It is inexcusable that anybody should be sent to their death, let alone sent to their death for a crime they have no way of proving their innocence of. China must supply us with details of the crime at least if they expect us to go around existing legislation which does not provide for extradition,' she said. The Constitutional Court's decision was supposed to have been delivered last month.