Under Section 104 of the Bharatiya Nyaya Sanhita, 2023, a person who, being under sentence of imprisonment for life, commits murder shall be punished with -

Section 104 of the BNS deals with the punishment for murder committed by a life-convict and provides that whoever, being under sentence of imprisonment for life, commits murder, shall be punished with death or with imprisonment for life, which shall mean the remainder of that person's natural life. The provision departs from Section 303 of the Indian Penal Code, 1860, which imposed a mandatory sentence of death for murder committed by a life-convict. The BNS makes the punishment discretionary, between death and imprisonment for the remainder of natural life, thereby complying with the constitutional requirement recognised in Mithu v. State of Punjab that the sentencing discretion cannot be wholly excluded.