Rights advocates are worried that a watered-down regulation on cleaning up the detention system passed last month still gives police too much room to continue existing abuses.
Mainland media said this week the State Council passed the Detention Centre Regulation on February 15 and it would come into effect next month.
The government regulation - one level weaker than a national law - applies to administrative and judicial detentions only, where detainees are normally punished for breaching public order or a court order, and are locked up for 15 days at most.
Detention of criminal suspects can last much longer and they are held in facilities known as kanshousuo (criminal detention houses).
The new regulation on administrative and judicial detention bans police from forcing detainees to work and from insulting, beating and torturing them. The regulation also demands the 'timely' notification of family members when a person is detained, and says special approval must be obtained if a person is detained somewhere other than his hometown.
There has been a string of mysterious deaths of inmates in recent years, many later found to have been caused by illegal use of force by police or fellow inmates, sparking demands for reform. While most of the deaths have occurred in criminal detention centres, reports say at least two cases have been in administrative detention centres.
When it was released for public consultation, a 2009 draft of the regulation on administrative and judicial detentions won praise from mainland legal professionals for filling a loophole in the law and addressing some major concerns, such as the practice in some centres of using inmates to control inmates, which led to bullying.
But many of these improvements have been removed.
Most discussion online and in the media has focused on the removal of two clauses: one that said police would be criminally liable if they engaged in nine forbidden acts, including beating or stealing from inmates, and one which said family members must be notified about a detention within 12 hours.
Another clause since removed demanded that an investigation be carried out if an inmate died of unnatural causes at a detention centre.
Peking University law professor Zhan Zhongle said the clause on criminal liability of police was probably removed because it was only a regulation - as opposed to a law - and an amended version of the State Compensation Law passed in 2010 had dealt with the criminal liability of officers in such abuse scenarios.
But other legal professionals are worried that the retractions reflect the authorities' continued preference for strong police power.
Hong Kong-based legal researcher Joshua Rosenzweig said even if abuses in such detention centres were relatively rare, he could not understand why the clauses had to be removed from the regulation.
'If you look at these clauses, every single one of them placed a restriction on the police,' Rosenzweig said. 'This gives the impression that they are trying to avoid being held liable for things that go wrong.'