Mr Guan's anger over his own treatment has motivated him to help people with similar complaints and he has become something of a clearing house for local protesters.

Since the city stepped up the demolition of housing to clear space for new developments ahead of the 2008 Olympics, as many as 1,000 people have demonstrated almost daily outside City Hall or the Zhongnanhai leadership compound, demanding better compensation. Mr Guan is a regular.

Through the protests he has developed an informal network of people protesting against other land disputes, labour problems, Cultural Revolution grievances and assorted unsettled issues with the government.

'This is going on everywhere,' Mr Guan said. 'In Beijing, Shanghai and Tianjin.'

At least twice in any conversation with Mr Guan, he says that the level of discontent with officials at all levels shows that life was fairer under Mao Zedong.

'They can do anything without the law, without the court,' he said of the government.

Mr Guan says he has never organised a protest, but he often works on the sidelines. He is constantly on his mobile phone, putting protesters in touch with one another, calling the press and arranging to meet disgruntled citizens for lunch or cigarettes.

Last week Tan Zhenqi went to City Hall looking to complain about an incident in which she says police handcuffed her, then beat her 14-year-old son and took away his study materials.

Ms Tan said the violence broke out on July 1 after she discovered the demolition of her house. She was offered 30,000 yuan (HK$28,300) as compensation. Outside the gates of City Hall, Ms Tan ran into Mr Guan, who has taken up her cause.

'They don't give you a home, they don't give you any money,' Mr Guan said.

His activism stems directly from his outrage, said Xu Yonghai, a fellow protester.

'He's really mad about the house, and he's compassionate about issues of injustice,' said Mr Xu, who is protesting at the demolition of his parents' home.

Mr Guan says he is not scared of the authorities, despite the fact that people have been jailed for protesting. He was surprised when police questioned him on July 1 about his role in a Zhongnanhai protest that authorities foiled by blocking nearby intersections.

If anything, the attention has encouraged him to do more. On July 3, he acquired the police records of Qi Zhiyong, a June 4 amputee who was jailed last month for meeting a foreign reporter.

People should not be afraid to fight back, especially if they have little to lose, Mr Guan said. 'People still believe in the government, so there's still some hope.'

The central government tolerates the Beijing protests now to pressure local government agencies into shaping up, said Nicolas Becquelin, research director with the Human Rights in China advocacy group. But he said Mr Guan was still on shaky ground with police. 'Police will tell them they're keeping an eye on them,' said Mr Becquelin, speaking in general about China protest organisers.