WASHINGTON -- A Boston-based activist jailed in China said he would not appeal his five-year prison sentence on spying charges, because he considered both his trial and the verdict illegal.

Yang Jianli, 40, was sentenced by a Chinese court May 13, for allegedly entering China illegally and spying for rival Taiwan.

Yang, a Chinese citizen with permanent U.S. residency, denied the charges. And in a two-page letter released this week, he said his more than two-year imprisonment in China, the trial and the sentence have repeatedly violated his human rights and broken the law.

"In my view, the question of whether or not to appeal doesn't exist to me," said Yang, in a letter written in Chinese and translated by his wife's American lawyers. "This does not imply that I obey the illegal conviction. I simply refuse to be put on show any longer with the so called 'People's Court'."

Initially, Yang's wife, Christina Fu, said her husband would appeal his conviction. But Yang declined.

He said that he had not been allowed to communicate privately with his Chinese lawyer, that he had been detained illegally, and that the deadline for issuing a verdict in his case expired last December.

Yang was detained in April 2002 while boarding an airline flight in the southwestern city of Kunming with a fake identity card. He was in China meeting with dissidents and protesting laid-off workers. He was using a fake identity, his family said, because he was barred from entering China after helping pro-democracy activists in Beijing's Tiananmen Square.

The Chinese government contended he was spying for Taiwan.

Student leaders from the bloody 1989 Tiananmen Square crackdown by the Chinese military are commemorating the 15th anniversary of the protests this week, and are staging a hunger strike in Washington to draw attention to Yang's situation.

According to Fu's lawyer, Jared Genser, Yang will be eligible for parole after he has served half of his five-year sentence. Since he was given credit for the time already served, that would be Oct. 26.

Members of Congress and Bush administration officials have repeatedly called for his release and have talked with Chinese leaders about the case.