BEIJING — An array of activists, academics and dissidents are questioning the authorities' purge of Bo Xilai, demanding that China's legislature follow the rule of law and allow the disgraced leader to defend himself before lawmakers.
China's leadership is desperate to move beyond a scandal involving a former member of its Politburo that has drawn worldwide attention, and some say it is doing so at the expense of standard legal procedures.
Left-leaning supporters of Mr. Bo wrote an open letter to the National People's Congress urging it to allow Mr. Bo to have his say.
The petition has begun to draw broader and somewhat unlikely support, attracting signatures from exiled dissidents and rights activists who don't consider themselves in Mr. Bo's corner.
The legislature's standing committee was expected to expel Mr. Bo during its four-day meeting starting Tuesday, a move that would strip Mr. Bo of his legislative immunity and pave the way for his criminal prosecution, likely in a swift trial.
The letter, which also has circulated on activist websites that are blocked in China, urges the congress not to expel Mr. Bo until he has an opportunity to address allegations against him.
"They should give Bo a chance to defend himself. The procedure has to be just," said Zeng Yuan, a local rights activists from Chengdu who said he signed the petition even though he does not support Mr. Bo.
"A Politburo member has been silenced just like that? This has gone against what the constitution says about human rights," Mr. Zeng said by phone.
Mr. Bo was one of China's best-known politicians until he fell from grace earlier this year when a close aide disclosed that Mr. Bo's wife had murdered British businessman Neil Heywood.
He has been out of sight, presumably detained, since mid-March. He was expelled from the party last month.
Authorities have said they intend to charge Mr. Bo with obstruction of justice in connection with the Heywood murder, as well as corruption and illicit sexual affairs that go against Communist Party rules.
Mr. Bo's reputation for championing social fairness and communist nostalgia made him popular among poorer Chinese and those who identify themselves as members of the new left — believers in a strong authoritarian government that promotes more egalitarian economic and social policies.
But his maneuvering to reach the highest echelons of the Communist Party angered many in Beijing, while his campaign to promote Communist Party culture revived memories of the chaotic Cultural Revolution, Mao Zedong's radical experiment in class warfare to root out opponents of communism.
He also has been accused of trampling on civil liberties — making it all the more noteworthy that rights activists are coming to his defense. His anti-mafia crackdown in the city of Chongqing was rife with allegations of torturing suspects.
The open letter was drafted by Liu Jinhua, 77, a Bo supporter in the southwestern city of Leshan, who said the appeal was sent by registered mail to the legislature.
"Whether Bo Xilai broke the law or not should be based on facts; we ask for openness and fairness," Mr. Liu said. "We hope that in the handling of major events, like the Bo Xilai incident that has grabbed the attention of the world, we can promote China's rule of law."
Mr. Liu said organizers received hundreds of signatures by email and that it was not possible to verify the authenticity of all of them. At least 10 of the several hundred names already have been proven fake, he said, though he believed the vast majority of them were genuine.
The letter also criticizes government moves to block leftist websites and clamp down on dissenting voices in the Bo scandal.
"Are these not barbaric acts that flagrantly violate our constitution and laws and shameful acts that completely departing from the principle of the rule of law and the people's democratic spirit?" the letter says.
Mr. Liu elaborated in an email that efforts to shut down discussion of the Bo case appeared to subvert the legal system in order to carry out a political purge.
Signatories include Gong Xiantian, a law professor at the prestigious Peking University who confirmed in an email that he signed the letter.
Exiled dissidents Wang Xizhe and Gao Han, living in the U.S., also confirmed their signatures. Mr. Wang and Mr. Gao do not identify themselves as leftists.