China's top court is working to amend judicial documents to formulate stricter rules on the use of commutation, parole and temporary discharge for convicts serving prison sentences.

The new rules are expected to be released by the end of this year, Luo Zhiyong, a senior judge of the Supreme People's Court (SPC) in charge of judiciary work supervision, said at a press briefing on Wednesday.

Problems in granting parole, commutation of sentences or temporary discharge for disease, pregnancy or other conditions, which shorten prisoners' sentences, have drawn particular attention and criticism from the public in recent years, Luo said.

"The modifications will stipulate stricter requirements and procedures for commutation or parole decisions. They will also shorten or limit the possible margin for commuted sentences," Luo said.

The SPC also publicized five typical cases involving shortened prison terms, including one in which a commutation for a prisoner was canceled after reviews found the commutation decision had problems.

According to Teng Wei, also an SPC judge, the top court has established a long-term supervision system for the issue, which includes random checks of relevant cases and scrutiny of prison term reductions for convicted former officials.

Those found to have violated laws and regulations and improperly granted commutation, parole or other terms will be punished and the cases will be made public, Teng said.

Chinese public criticism has been strong in recent years against suspected corruption in commutation procedures, which may allow rich and powerful convicts to bribe their way out of jail.

The Supreme People's Procuratorate said earlier this year that foul play was found in 213 cases during a campaign that lasted from March to December of 2014 targeting justice officials who abused their power to grant parole, commutation or temporary discharge.