If you were to map an emotional topography of China, the valleys of grief and resentment would run deepest in the rubbish-strewn alleys of Fengtai, near South Beijing railway station. Even for a nation with hundreds of millions of hard-luck stories, the tales of rough justice, corruption and violence do not come much more pitiful; nor do they come as carefully typed, hand-written, photocopied in triplicate and personally sealed.
For this is the home of China's most desperate petitioners, the disaffected victims of local injustice -- real and imagined -- who come to Beijing to appeal to the central authorities.
Many are scarred, on crutches, blind or otherwise horribly maimed from industrial accidents, police beatings and acid attacks. Most complain of being cheated of their land by developers and bribe- taking officials. Others tell of daughters raped by village chiefs, and factory bosses running off with workers' redundancy money.
All have their papers. First is the official petition they present to the quaintly named State Bureau for Calls and Letters -- the closest thing the communist government has to a customer complaints center -- and then they hand as many copies as they can afford to anyone who looks influential enough to help.
"I'm here on behalf of a 1,000 villagers whose land was stolen by corrupt officials," said a Mrs Liu from Hongmin Town. "We've been beaten up, and my husband, who was elected as village chief by the local people, has been removed from office."
"I spent my life's savings on a gasoline station," said a Mr Liu (no relation) from Jiling Province, who runs a small inn.
"But one day the county chief got drunk and ordered his henchmen to smash it up."
"I've been petitioning for four years, but never yet had a chance to meet any of the officials looking at my case. The police have arrested me several times, though," he said.
Mr Sun, of Gansu Province, said: "The bosses kept the compensation money when our uranium-processing factory was closed."
"They are corrupt, they are polluting local rivers and risking the health of the workers," he said.
"Please, will you solve my case," implored a woman who had arrived five days earlier with her daughter from Liaoning, 644km to the northeast, to file a land claim.
In their short time in Beijing, they said they had already been beaten by the guards outside the bureau, and they lived in fear of being picked up by police from their home town and sent home.
Their concern is justified. Many of the guests of the nearest big hotel -- the Taoran Dasha -- are public-security officers from the provinces, who come to hunt down local "trouble makers" before they can present their petitions.
This is particularly true in March -- the most politically sensitive time of year -- when Beijing hosts the National People's Congress.
China's 10-day annual parliament is a tiny window of opportunity for petitioners, who try to have their cases heard by state leaders and the 3,000 local representatives.
But, as is the case every year, the police have rounded up tens of thousands of petitioners. Many have been sent home.
The petitioners are, indeed, potential troublemakers. They have little choice. In most cases they are the victims of people with power -- communist cadres, factory bosses and municipal leaders. In the absence of an effective legal system, their only chance is to create the biggest possible bureaucratic headache for their tormentors.