Although the 1982 constitution guarantees freedom of speech, the Chinese government often uses the "subversion of state power" and "protection of state secrets" clauses in their law system to imprison those who criticize the government. Another crime used to jail critics such as Sun Dawu is "picking quarrels and provoking trouble".

During the 2008 Summer Olympics, the government promised to issue permits authorizing people to protest in specifically designated "protest parks" in Beijing. However, a majority of the applications were withdrawn, suspended, or vetoed, and the police detained some of the people who applied.

References to certain controversial events and political movements, as well as access to web pages considered by the PRC authorities to be "dangerous" or "threatening to state security", are blocked on the internet in the PRC; and content disputed by or critical of PRC authorities is absent from many publications, and subject to the control of the CCP within mainland China. Laws in the People's Republic of China forbid the advocacy of separation of any part of its claimed territory from mainland China, or public challenge to the CCP's domination of the government of China. An unsanctioned protest during the Olympics by seven foreign activists at the China Nationalities Museum, protesting for a free Tibet and blocking the entrance, was cleared and the protesters deported.

Foreign Internet search engines including Microsoft Bing, Yahoo!, and Google China have come under criticism for aiding these practices. Yahoo!, in particular, stated that it will not protect the privacy and confidentiality of its Chinese customers from the authorities.

In 2005, after Yahoo! China provided its personal emails and IP addresses to the Chinese government, reporter Shi Tao was sentenced to imprisonment for ten years for releasing an internal Communist Party document to an overseas Chinese democracy site. Skype president Josh Silverman said it was "common knowledge" that TOM Online had "established procedures to...block instant messages containing certain words deemed offensive by the Chinese authorities". In June 2020, the European Union demanded an immediate release of Yu Wensheng, who after two years in detention, was sentenced on charges of “inciting subversion of state power”, for writing an open letter demanding constitutional reforms.

On 24 July 2020, the CCP expelled an outspoken and influential property tycoon, Ren Zhiqiang, who denounced the country's authoritarian leader, CCP general secretary Xi Jinping. He went missing in March after criticizing Xi, and later his case was passed to the judiciary system for criminal investigation.

On 29 July 2020, the Chinese government begun applying the new National Security Law to suppress peaceful speech, curtail academic freedom, and generate a chilling effect on the fundamental freedoms in Hong Kong.

On 11 August 2020, Human Rights Watch demanded Chinese authorities on the basis of security law to immediately release the 10 democracy supporters and activists arrested on 10 August and drop all vague “national security” charges imposed on them.

In June 2020, Cai Xia, a retired professor of CCP's Central Party School, criticized Xi Jinping, the General Secretary of the CCP, called him a "mafia boss" and the ruling Communist Party a "political zombie". In a 20-minute audio on social networking sites, she said that everyone is Xi's slave, and there is no human rights and rule of law, She suggested that Xi should retire. On 17 August 2020, Cai Xia was expelled from the CCP's Central Party School and her retirement pensions were cancelled.