Legal professionals have called for stricter supervision of police officers when questioning suspects during their first 24 hours at police bureaus to prevent forced confessions and reduce wrongful convictions.

Lawyers and law professors attending a seminar in Beijing on Wednesday praised the efforts the country has made to eliminate illegal evidence, but called for the further tightening of related regulations.

Chinese law allows police to summon individuals for interrogation for up to 12 hours, but this may be extended to 24 hours for serious or complicated cases.

Li Fenfei, a professor who specializes in legal procedures at Renmin University of China, said that torture is most likely to occur shortly after people are summoned to police bureaus and before they leave or are taken to detention houses.

The Criminal Procedure Law, which was revised in 2012, has specific stipulations on forced confessions, requiring all interrogations to be recorded by video and audio. It also states that evidence obtained illegally has no legal relevance and cannot be used in trials.

“The law represents the progress China has made in protecting human rights and reducing forced confessions, but it mainly targets behaviors in detention houses, and doesn't clearly regulate police behaviors in suspects' first 24 hours at public security departments,” Li said.

Wang Chao, a law professor at Beijing Normal University, said suspects are physically separated from investigators when they are interrogated in detention houses, “but similar measures are not adopted in police bureaus”.

He called for the introduction of a law to ensure there are lawyers on duty at police stations to better supervise police behaviors in the first 24 hours of questioning.

Yang Limin, a criminal lawyer in Beijing, said that forced confessions are most likely to take place in the first 48 hours of questioning at police bureaus because police are under pressure to solve cases and they lack interrogation skills.

Wang Zhenhui, a law professor at China University of Political Science and Law, said that his institution has conducted experiments since 2003 involving the deployment of lawyers at police stations. “It's necessary for prosecutors to increase supervision of police behaviors,” he said.

Li Yixian, another lawyer, said that preventing forced confessions is the first step to reducing wrongful convictions.