Mr Shahbazi, now 20, was 17 when he was arrested for fatally stabbing a schoolmate during a fight involving four people.
He was scheduled to be executed on January 5, which was temporarily halted.
Respect international law
Experts said the court relied in part on confessions allegedly obtained under torture and ill-treatment when Mr Shahbazi was interrogated by police for 11 days.
During this period, he was also denied access to a lawyer and his family.
“We urge the Iranian authorities to immediately and permanently suspend the execution of Hossein Shahbazi and quash his death sentence, in accordance with international human rights law,” the experts said in a statement.
They added that Mr. Shahbazi’s execution was to take place four times, causing him and his family irreversible psychological pain and suffering.
UN experts previously raised concerns about the death sentence and impending execution with Iranian authorities on June 7, 2021 and again the following month.
The Government replied that a reprieve had been granted to facilitate reconciliation in view of the pardon.
“We re-emphasize that reconciliation efforts do not replace the government’s obligation to prohibit such executions,” the experts said.
“International law unequivocally prohibits the imposition of the death penalty on persons under the age of 18. Iran must respect its international obligations by imposing a de jure and de facto moratorium (it really should be a moratorium, but since this is a direct quote, they can take the grammatical rap) on the execution of offenders juveniles once and for all.”
More than 85 juvenile offenders are currently on death row in Iran, according to experts.
Last November, the UN human rights office, OHCHR, condemned the execution of another juvenile offender, Arman Abdolali, 25, accused of murder when he was 17.
OHCHR also lamented that Mr. Abdolali was transferred to solitary confinement six times before his scheduled execution, which was postponed each time before his hanging on November 24, 2021.
Role of UN experts
The experts who issued the statement are Javaid Rehman, special rapporteur on the situation of human rights in Iran; Mikiko Otani, President of the Committee on the Rights of the Child; Morris Tidball-Binz, Special Rapporteur on extrajudicial, summary or arbitrary executions, and Nils Melzer, Special Rapporteur on torture and other cruel, inhuman or degrading treatment or punishment.
They receive their mandates from the UN Human Rights Council in Geneva, and are not UN staff and are not paid by the Organization.