Nine years ago, Chen Junyu was deputy head of a town police station in Guangzhou's Baiyun district and a rising star in the force, known for his tenacity and skill. Now he is using those talents for a very different purpose, to become a big thorn in the side of the Guangzhou authorities. Chen came under heavy police surveillance last month, as the city increased security ahead of this month's Asian Games. 'I've been watched by three plain-clothes officers around the clock every day,' Chen said. 'But they are no match for me because I'm far more experienced.' He can lose a police tail in just a few minutes, using a subway station near his Baiyun district home, and also knows how to shake off those monitoring his cell phone. Within an hour he can reappear at a Haizhu district restaurant, meeting with activists to plan a new protest in the city's People's Park, opposite the municipal government building. Protesting outside the government headquarters has become a regular thing for members of the Human Rights Protection Association - laid-off workers, low-income families, veterans and others - since 2003. 'We feel free and safe, as no one can disturb us when Ah Chen is here,' said one unemployed woman. 'He taught us how to avoid being followed and monitored, and all his ideas work. Now we are all anti-surveillance experts.' Besides his anti-surveillance skills, Chen also provides free legal aid to vulnerable groups fighting for their rights. 'Actually, I just teach them how to protect themselves, because almost all those in vulnerable groups are poorly educated people who lack legal knowledge,' Chen said. 'I help them because I sympathise with them as a fellow victim of our legal system, which I've discovered is far more corrupt and unjust than I could ever have imagined.' Chen, now 39, was kicked out of the force seven years ago after being jailed for a year for bribery - an allegation that he says came from a colleague who was tortured during interrogation about another bribery case. And he says his downfall stemmed from retaliation for his 'excessive hard work'. Chen was a model police officer during a clampdown on the sex industry in early 2001. During a routine patrol on March 27 that year, he noticed a lot of people entering and leaving a residential complex. He went inside to investigate and came across three men with prostitutes. He discovered that two of the three men were senior police officers after taking them to the police station for questioning. 'Two of the three clients were former Baiyunshan police sub-bureau deputy director Zhang Ruiyun and Guangzhou police officer Wang Yong ,' Chen said. 'Both were my superiors.' The third man was Zou Tiejun , a senior official in the Guangzhou Industry and Commerce Bureau. Chen ordered the three men to write self-criticisms and passed the two police officers onto their work units for follow-up action, in accordance with internal disciplinary regulations. 'I was firmly sticking to our law, but it made me the target of retaliation,' Chen said. In October 2002, one of his former subordinates was arrested for stealing public assets to cover gambling debts. He confessed but also accused Chen of taking 25,000 yuan from Zhang, Wang and Zou to make the prostitution incident disappear. Although statements from the three men made no mention of giving any bribes to Chen, he was summoned by the municipal police bureau's disciplinary committee weeks later for a month-long interrogation that shocked him to the core. 'I never expected that they would use the same methods, including starvation, sleep deprivation and around-the-clock questioning, that they applied to counter-revolutionaries during the Cultural Revolution to force me to confess,' Chen said. 'Finally, I lost control and jumped out of a custody-room window on the ninth floor after being tormented for three days.' He suffered head and leg injuries but scaffolding on the third floor of the building saved his life. However, he says he was only sent to hospital after writing a self-criticism admitting that he was 'fleeing punishment'. His wife was told to come up with a 25,000 yuan deposit for hospital treatment - money that was used as evidence of bribery. Before a hearing in the Baiyun District People's Court on May 12, 2003, Chen was told by a police officer that if he pleaded guilty the court would just give him a disciplinary sanction such as a demotion, otherwise he was facing seven years in jail. Chen decided to try for a compromise but three months later he was jailed for nine months. 'I found I was tricked and vowed to appeal,' Chen said, even though he was warned that could make matters worse. His challenge resulted in another court verdict the next day, with the prison term increased to a year, including time already served since his arrest. The other details, including the date, judge, court staff and file number remained unchanged. Chen was dismissed from the force and expelled from the Communist Party while in jail. When he was released on December 15, 2003, he discovered that his wife had left him and taken their daughter with her. He spent the next four years gathering evidence to prove his innocence, including original copies of his two verdicts and copies of the three officials' self-criticisms. On June 4, 2007, the Baiyun court agreed to rehear his case. A member of the court's staff said the first hearing had not applied the correct legal procedures and that the officials responsible had been punished. But the court twice turned down Chen's requests to transfer his case to another district court and allow in overseas media. In protest, Chen refused to appear. In March this year, the municipal politics and law committee promised to arrange a third hearing, but he's still waiting for it to take place. 'I absolutely understand why police killer Yang Jia would take such an irrational action, as I have experienced the same helplessness in our legal system,' he said, referring to the man who was executed in November last year for murdering six Shanghai police officers. 'I got nothing after spending seven years seeking justice even though I collected all necessary evidence. 'If I were not the father of an 11-year-old girl, I could make a powerful explosive and perish together with those involved in my case because I was well trained. But my rationality tells me no to do that.' The Asian Games have given Chen and many other activists in Guangzhou hope that their grievances can be aired more widely. 'I am waiting for a chance as I believe justice can be achieved only under the scrutiny of the media, especially overseas media in Guangzhou to cover the Asian Games,' he said. 'We will definitely to show the real face of our city to the overseas media during the Games, but it makes our authorities very nervous.' Chen said the city's veteran petitioners, including laid-off workers, the homeless who lost houses to make way for Asian Games venues, low-income families and others, had been warned by the authorities to keep silent during the Games. Besides warnings, Chen said the Baiyun District People's Court and related government officials had also tried to bribe him. 'I know that they [government officials] will continue to try to wear down my willpower by all kinds of tactics,' he said. 'But I am not a fool any more. I will not be trapped this time. I still believe my name will only be really rehabilitated through formal legal process.' Thanks to his police school training, Chen is able to earn a livelihood in today's Guangzhou with his knowledge of information technology and good command of English. 'I never expected that what I learned at the police school would be become a practical weapon today in dealing with the authorities,' he said. 'It was definitely a windfall for me.'