What you need to know

• Ms. Pike was denied clemency and, one hour before her execution, a court halted it then lifted the stay
• She was twice injected with lethal drugs and survived
• Calls are growing for authorities to commute Ms. Pike’s death sentence

“The prolonged suffering – physical and mental – arising from multiple failed execution attempts is abhorrent and cruel,” Volker Türk said in a statement.

The UN rights chief pointed to unresolved questions surrounding Ms. Pike’s fair trial, saying they raised additional concerns about proceeding with another execution attempt.

The statement comes amid what the UN office described as an increase in the number of executions in the United States, with the Pike case renewing attention to the human rights implications of capital punishment in the country, including safeguards for fair trials and the treatment of people subjected to repeated execution attempts.