A Tennessee execution failed to kill the condemned woman, reviving hard questions about whether states and doctors can reliably end a life without suffering — bad news for defenders of lethal injection and of assisted-death programs.

• Christa Pike, sentenced to death for a 1995 murder, survived two rounds of lethal drugs and was taken to a hospital, possibly brain damaged.
• Witnesses reported she was still breathing loudly an hour in, and she asked staff why her arm felt like it was about to explode.
• Republican Governor Bill Lee has halted all Tennessee executions and ordered an independent review, calling the case deeply disturbing.
• Her lawyer had warned that a lifelong blood disorder made it hard to get needles into her veins; the same doctor is reported to have been involved in an earlier botched execution.
• Critics of Canada's assisted-death program, including author Kelsey Sharon, argue its official 1.8% complication rate is meaningless because doctors report on themselves, and point to cases of patients waking mid-procedure.

Outlook: Expect the Tennessee review to stall executions there for months while the botched case fuels wider fights over assisted dying in Canada and Europe.