The latest draft of the supervision law applying to public servants has introduced new measures to protect the rights of graft suspects, such as informing family and employers of detainees within 24 hours of detention.

Exceptions can only be made when there is danger of collusion, evidence or witness tampering or other forms of obstruction to the investigation, according to the draft submitted to the top legislature for second review on Friday.

Compared with the first draft submitted to the Standing Committee of the National People's Congress in June, the latest version also narrows the application of "measures of technical investigation", which could include monitoring and surveillance, to suspected "major graft cases" instead of the previous "major cases of graft and dereliction of duty".

It also requires a timely lift of such measures if there's no longer a necessity.

In addition, frozen assets should be released under the latest draft within three days of being found irrelevant to the case.

A draft law usually needs to undergo three reviews before being adopted. Laws that affect the fundamental system of the country need to be deliberated at an annual plenary session of the NPC.

The draft supervision law is widely watched, since it is designed to replace the practice of shuanggui, an intra-Party disciplinary practice, exercised by Party disciplinary officials, in which Communist Party of China members under investigation must cooperate with questioning at a set time and place.

China announced its decision to replace the practice of shuanggui with detention during the 19th National Congress of the CPC in October, as reform of the national supervision system deepens.

Ruan Chuansheng, a law professor at the Shanghai Administrative Institute, said the clarified and regulated procedures in the draft law are key to the protection of the rights of detained people.

"I'm glad to see investigators are ordered to inform the detainees' families and employers in a timely manner, as it will safeguard the detained and reinforce investigators' obligations," he said.

Ruan said the draft law is to make the nation's fight against corruption more scientific and according to rule of law.

Ma Huaide, a law professor at China University of Political Science and Law, suggested further regulating the interrogation process by requiring that interrogations be recorded 24 hours a day, seven days a week, and the recording should be delivered to judicial departments in order to better protect the rights of those questioned.