Former Taiwanese president Chen Shui-bian has formally appealed against a verdict sentencing him to life in jail for corruption, in a fresh attempt to redeem his integrity and stage a possible political comeback. But the prospect of a comeback was undermined by an announcement yesterday from the pro-independence Democratic Progressive Party - of which he was once chairman - barring him from returning to the party in the next five years. Through his chief aide Liu Tao, Chen said he had filed an appeal with the Taiwan High Court. Liu said: 'The former president also clearly said he would give up his rights for lawyers to defend for him in the event of any biased move made by the High Court, including deliberating assigning a judge to handle his case.' Chen was convicted by the Taipei District Court along with his wife, Wu Shu-chen, of embezzlement, accepting bribes, money laundering, influence peddling and other offences during his two terms in office between 2000 and last year. He had repeatedly denied all charges, saying the trial was politically motivated by mainland-friendly Taiwanese President Ma Ying-jeou, who wanted to lock him up to appease Beijing for his persistent push for Taiwan independence. The appointment of district court judge Tsai Shou-hsin, whom Chen claimed was highly biased, to handle the case was cited as proof of a 'political trial'. Under a longstanding practice, the island's judiciary rarely designates a judge to handle any particular court case, to avoid being accused of partiality, and a judge is given a case only by drawing lots. Chen might have received a different verdict after he was indicted in December if judge Chou Chan-chun, who released him without bail, had not been replaced by Tsai. Tsai backed a prosecutors' appeal against Chou's ruling and sent Chen back to the detention centre. High court spokesman Wen Yao-yuan said: 'We will go by the practice of drawing lots in order to be open, fair and just.' This meant Chen's appeal could fall on any of the 86 high court judges, Wen added. Chen's lawyer, Cheng Wen-lung, said if the high court was able to maintain its impartiality, Chen stood a better chance of being released and clearing his name. Chen had declared that once he was released, he would step up efforts to promote the independent status of Taiwan - a vow that has won applause from his supporters. But his attempt to stage a political comeback by proclaiming himself as the leader of the pro-independence camp apparently hit a snag after the DPP said he had been expelled. 'Once he was convicted guilty by the district court, his membership was automatically removed by the party in line with a DPP disciplinary decision on October 9 [last year],' DPP spokesman Chao Tien-lin said. Chao said that under the party's rules, if a member was expelled, he or she was not eligible to apply for membership in the next five years. Chao yesterday also asked supporters to remain rational over the verdict after local media said the judge, Tsai, and other judicial officials involved had received death threats. Instead of massing supporters to protest against the verdict, the DPP has merely asked for the release of Chen in what the media said was a move to distance itself from the former president ahead of the local elections at the end of the year. On Sunday, former vice-president Annette Lu Hsiu-lien even called on Chen and his family to apologise to his supporters.