The Appellate Division of the Supreme Court has ruled that life imprisonment means a convict will remain behind bars for 30 years and will get remission and deduction benefits under relevant laws if it is not specifically mentioned in the verdict that the convict is sentenced to imprisonment until natural death.

However, the apex court yesterday said the imprisonment for life apparently means a convict's jail sentence for the rest of his or her natural life.

If the courts concerned, including the International Crimes Tribunal, sentence a convict to imprisonment for life until natural death, he or she will not get the benefits under the Penal Code and the Code of Criminal Procedure (CrPC), the SC observed in a short verdict.

"Imprisonment for life in prima facie case means the entire remaining period of the convict's natural life. Imprisonment for life be deemed to equivalent to imprisonment for 30 years if sections 45 and 53 are read together along with sections 55 and 57 of the Penal Code and 35A of the Code of Criminal Procedure."

However, in case of a convict awarded life imprisonment until his natural death by the court/ tribunal, International Crimes Tribunal under International Crimes Tribunals Act, 1973, the convict will not be entitled to get the benefit of section 35A of the Code of Criminal Procedure, the apex court said.

A seven-member bench of the Appellate Division, headed by Chief Justice Syed Mahmud Hossain, delivered the verdict by a majority decision following a review petition filed by a convict, Ataur Mridha.

The SC did not disclose the names of its judges who gave their consent to the decision and who differed.

Interpreting the short verdict, Attorney General AM Amin Uddin told reporters that if the court concerned sentences a convict only to life imprisonment and does not say imprisonment until death, he or she will have to serve in jail for 30 years and will get remission benefits.

If the court sentences a convict to an imprisonment until death, he or she will have serve in jail for the rest of natural life, the AG added.

Speaking to The Daily Star, Ataur's lawyer Mohammad Shishir Manir said there are more than 5,000 prisoners who have been convicted and sentenced to life imprisonment by courts. The prisoners will have to serve in jail for 30 years and they will get remission of seven and a half years. Also, the tenures already served by them in jail will be deducted from the 30-year jail sentence, he added.

He said the SC in its short verdict did not disclose whether his client Ataur would have to serve in jail until his natural death.

This issue will be cleared once the SC releases the full text of the verdict, Shishir added.

Ataur had filed the review petition challenging an apex court verdict that on February 14, 2017 commuted his death penalty to life imprisonment in a murder case.

The Appellate Division bench, headed by the then chief justice Surendra Kumar Sinha, had said life imprisonment means jail sentence until natural death of the convict.

Ataur submitted the petition to the SC seeking review of its judgment the same year. He said in the petition that under Section 57 of the Penal Code, life sentence refers to 30 years' prison term, which becomes 22.5 years after remission of seven and a half years.

During the hearing on the review petition, the apex court had earlier heard expert opinions from four amicus curiae (friends of court) -- senior lawyers AF Hasan Ariff, Rokanuddin Mahmud, Abdur Rezak Khan and AM Amin Uddin -- on the issue.

Lawyers Khandker Mahbub Hossain and Shishir appeared for the petitioner while Attorney General AM Amin Uddin argued for the state on November 24.