There is no humane way to execute

Following a news item posted below concerning a failed execution in Ohio, USA:
Ohio plans execution method untried on prisoners
COLUMBUS, Ohio — Ohio announced plans to switch from the usual three-drug cocktail used to execute inmates to a one-drug method which has never been tried on prisoners.
Under the three-drug method, the first drug makes the prisoner unconscious, the second paralyzes him and the third stops his heart — a process that death penalty opponents argue is excruciatingly painful if the first drug doesn't work.
The single-drug technique amounts to an overdose of anesthesia.
Death penalty opponents hailed the decision as making executions more humane but expressed reservations about using such an untested method. The same drug is commonly used to euthanize pets and in some parts of Europe has been used in assisted suicides.
Richard Dieter, director of the nonprofit Death Penalty Information Center, noted the new practice would essentially be an experiment performed on inmates.
"They're human subjects and they're not willingly part of this," Dieter said. "This is experimenting with the unknown, and that always raises concerns."
The inmates who are going to be executed could challenge the constitutionality of what's being proposed in Ohio.

The lesson for Thailand is that there is no humane way to kill people