In a statement on Monday, Agnes Callamard, the UN Special Rapporteur on extrajudicial, summary or arbitrary executions, and Nils Melzer, the UN Special Rapporteur on torture and other treatments or punishments, expressed concern that Doyle Lee Hamm, who is due to be executed in Alabama on Thursday, may not have received a fair trial, reports Xinhua news agency.
Hamm, 60, been on death row since 1987. He was convicted in 1987 of murdering a hotel clerk during a robbery and he reportedly confessed to the murder.
He has been diagnosed with lymphatic cancer and basal cell carcinoma.
According to a UN report, medical professionals have had difficulties accessing his veins due to the cancer.
"We are seriously concerned that attempts to insert needles into Hamm's veins to carry out the lethal injection would inflict pain and suffering that may amount to torture," said the UN rights experts.
The statement also noted that judges have ordered a fresh medical report to be delivered by Tuesday.
"We urge the authorities to halt Hamm's execution, annul his death sentence, and hold a re-trial that complies with international standards, as we have received information indicating that his original trial did not fully respect the most stringent due process and fair trial guarantees," they added.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
