What the death penalty means in the US now: botched executions:
An [Oklahoma prison] inmate whose execution was halted today because the delivery of a new drug combination was botched died of a heart attack, the state Department of Corrections said.
Director Robert Patton said inmate Clayton Lockett died after all three drugs were administered.
Patton halted Lockett's execution about 20 minutes after the first drug was administered. He said there was a vein failure.
Lockett was writhing on the gurney and shaking uncontrollably.
According to another source, the execution was stopped after the victim sat up 40 minutes after injection and said "something's wrong".
The reason for this mess: back in 2011, the European Union banned export of murder drugs to the US. When the stockpile ran out, states scrambled to source them elsewhere, resorting to untested combinations of probably impure drugs, resulting in several botched executions which did not meet US constitutional standards against "cruel and unusual punishment" (in the US, the state can murder you, but only if its "humane" about it, which is a contradiction in terms). To avoid constitutional challenge on those grounds, Oklahoma refused to say what drugs it was using and where it was sourcing them from. And now we have the result: another person dying in agony. Sadly, this will probably be seen as an improvement on the process by America's sadism and revenge lobby.