Beijing, China (CNN) -- Prominent Chinese dissident Liu Xiaobo, who was arrested in 1989 for his role in the Tiananmen Square protest, will be sentenced this week after a one-day trial in a separate subversion case, his attorney said Wednesday.
Shang Baojun, Liu's lawyer, told CNN that the trial was finished, and sentencing was scheduled for Friday. Liu has been accused of "inciting subversion" by Chinese authorities.
A few dozen supporters of Liu gathered outside the courthouse, waving signs and wearing placards.
Liu, a former university lecturer and literary critic, faces a possible 15-year jail sentence, amid growing international outrage over his year-long detention, according to media reports.
On Monday, the Times of London quoted Liu's wife, Liu Xia, as saying, "I have no hope whatsoever, I can't even attend the trial."
She told CNN Wednesday that police prevented her from leaving their home.
She said she planned to wait outside the courthouse.
"I think he will be sentenced to more than 10 years," she said.
Liu, 53, was detained on December 8, 2008, and held under "residential surveillance" as police investigated the case, according to the PEN American Center, a U.S. literary and human rights organization. On June 23 of this year, he was arrested and charged with inciting subversion of state power, the organization said. Liu is on the PEN board of directors.
The case was turned over to the prosecutor's office on December 8 -- one year from the time Liu was detained.
Liu co-authored Charter 08, "a declaration calling for political reform, greater human rights, and an end to one-party rule in China that has been signed by hundreds of individuals from all walks of life throughout the country," PEN says on its Web site. The group said Liu was arrested before the formal release of Charter 08.
"Liu has been engaged in agitation activities, such as spreading of rumors and defaming of the government, aimed at subversion of the state and overthrowing the socialism system in recent years," according to a police statement reported by China's state-run Xinhua news agency.
The statement claimed Liu confessed to the charge during a preliminary police investigation.
Liu served as an adviser to student leaders during the demonstrations at Tiananmen Square in 1989. Along with three other intellectuals, he took part in hunger strikes there on June 2 of that year prior to the crackdown to show support for the flagging student protests.
He was arrested two days after the Tiananmen crackdown and was released in 1991. In May 1995 he was detained again for collecting signatures for a petition calling for human rights guarantees.
The U.S. government has pressed for Liu's release.
"The U.S. government is deeply disturbed by reports that Liu Xiaobo has been formally arrested and charged with serious crimes," said Richard Buangan, deputy spokesman at the U.S. Embassy in Beijing, following Liu's latest arrest.
"We call on the government of China to release Mr. Liu and respect the rights of all Chinese citizens who peacefully express their desire for internationally recognized freedoms."