As time passed, Wu and his colleagues came to a series of surprising conclusions about the men and women shutting down their Web site.
First, the Internet service providers didn't seem to care until police stepped in. State regulations require the providers to monitor the sites they host, save data about the users who visit them and ensure that discussion sites are registered with the government. But the companies appeared more interested in winning customers than screening them.
There was a pattern to the behavior of the police too. It would have been possible to track down Wu and his partners, given the electronic trail they left by renting the server space and using it regularly. But the police didn't seem interested. The officers were usually in the same city as the Internet service provider, and they rarely left the jurisdiction.
It also would have been easy for the authorities to shut down the site quickly. Wu gave out the new address to anyone who asked. But the site often stayed open for weeks before police acted.
"The party is not a monolithic block," Wu said. "The police may feel, 'If we can avoid the trouble, let's avoid the trouble.' No one wants to go out of their way to hurt people."
Many officers and officials appear more concerned about profiting from the Internet than policing it. For example, a campaign to regulate Internet cafes has faltered because local authorities often look the other way when cafe managers fail to record customers' names or install surveillance software, as long as they pay taxes and fees.
"There are more and more of us mice, but the cat, for various reasons, is less interested in its work," said one of Wu's partners, a woman who helps manage Shanghai's economy. Another partner, a computer technician in Nanjing, added, "The cat is too busy making money."
'We're Not Going to Stop'
Wu said he cannot compete with the government's resources or its access to high technology. When he attempted to establish the site on a server overseas last year, for example, the authorities blocked users in China from seeing it. But Wu said he and his friends are more committed to their cause.
In December, they took the fight to a new level, organizing a petition drive on the site for the first time. Wu drafted an open letter calling for the release of Du Daobin, a regular writer on their site who had been arrested and charged with "inciting subversion against the state" after posting essays supporting last year's protests in Hong Kong. "This is a case of criminalizing speech," Wu wrote, urging the government to clarify the nation's subversion laws and stop using them to "suppress the people from carrying out peaceful criticism."
Wu circulated the petition among liberal intellectuals and legal scholars, who made improvements, then posted it on his site on Feb. 1. Police were slow to respond, and it quickly drew more than 1,400 signatures.
About two weeks later, Wu noticed that someone had deleted pages from the online petition. Then people began to have trouble accessing other pages on the site. Messages appeared telling users that essays were inaccessible because they contained "illegal phrases." Some indicated "Communist Party" was an illegal phrase.
On Feb. 19, the site was shut down. The Internet firm hosting it said it had acted under orders from the Ministry of State Security. Since the beginning of March, the site has opened and closed five more times.
"We're not going to stop," Wu vowed. "We'll try again in a few days."