Can you believe this?

So in the newspaper (USA Today) delivered to my hotel door this morning is an article about the Supreme Court upholding the right of States to use lethal injection for executing prisoners sentenced to death.
The issue was that prisoners in Kentucky had appealed to the court that the process was unjust in the eyes of the constitution as it was "cruel and unjust" because it caused unnecessary pain.
A Chief Justice quoted that to be successful, the prisoners would have had to show that the process "presented a substantial risk of harm to the prisoner".

EXCUSE me is death not a substantial risk of harm?!!!!!!!!