Chiranuch Premchaiporn, manager of the Prachatai website, faces up to 20 years' imprisonment on 10 separate charges of failing to promptly remove from the website offending comments posted by readers.
The 2007 Computer Crime Act addresses hacking and other traditional online offenses, but also bars the circulation of material deemed detrimental to national security or that causes public panic. Several people have been prosecuted under the law, but Chiranuch is the first webmaster to be tried, and her case has garnered the attention of free speech advocates around the world.
Thailand's freedom of speech reputation has taken a battering in recent years, as successive governments have tried to suppress political opposition. Its standing in the Press Freedom Index issued by the Paris-based group Reporters Without Borders slid to 153 last year from 65 in 2002, when the ratings were initiated.
Prachatai, which was founded by several respected journalists, senators and press freedom activists to serve as an independent, nonprofit, daily Internet newspaper, has often run afoul of the government.
Police arrested Chiranuch in March 2009 for an offense that allegedly occurred five months earlier. The controversial comments posted by members of Prachatai's webboard were said to have defamed the country's monarchy. She was accused of not deleting the comments for several days.
"I'm not sure if Prachatai was targeted specifically," Chiranuch told The Associated Press earlier this week. "All I can say is, given the circumstances, we were doing our job as we would normally do."
Prachatai was one of scores of websites the government barred access to last year during political unrest in Bangkok that turned violent and left about 90 people dead. The government claimed the sites stirred up unrest among the so-called Red Shirt protesters who were calling on Prime Minister Abhisit Vejjajiva to hold early elections.
Supinya Klangnarong, a media reform activist, said that the Computer Crime Act "has become a political tool of the state to close down websites and arrest people.
"The Thai state has been intensely using the act as political punishment, instead of curbing actual computer-related crimes," she said.
Chiranuch late last year was charged with another set of offenses, including lese majeste - defaming the monarchy - another controversial area of law. Thailand's lese majeste law mandates a jail term of three to 15 years for "whoever defames, insults or threatens the king, the queen, the heir to the throne or the regent."
Critics say it is mostly used as a weapon by political opponents to try to punish each other, since almost any critical comment touching on the monarchy can be construed as disloyalty to the institution. As in Friday's case, Chiranuch denies breaking the law.