Lethal Injection

History: In 1982, the United States became the first country on Earth to perform executions by lethal injection as a means of capital punishment. China became the second in 1997, and several other countries have since followed suit. Lethal injection is by far the most common type of execution in the United States--all executions in 2005, and all but one execution each in 2004 and 2006, were by lethal injection.

Unsavory Overtones: Nazi Germany used lethal injection as part of its T-4 Euthanasia Program as early as 1940, though it was later replaced by poison gas.

How It Works: The executioner, usually a person injecting the drugs manually (lethal injection machines are no longer in widespread use due to the possibility of mechanical failure), injects three drugs in sequence:

1. 5g Pentothol (sodium thiopental), which is intended to induce a coma.
2. 100mg Pavulon (pancuronium bromide), which causes paralysis.
3. 100 mEq potassium chloride, which stops the heart.

Complications: Pentothol does not always induce a coma, leaving the disturbing possibility that at least some prisoners killed by lethal injection may experience extreme pain due to the administration of potassium chloride--without any means of expressing that pain, thanks to the paralysis brought about by the Pavulon. For this reason, the U.S. Supreme Court ruled in Hill v. Crosby (2006) that death row prisoners may challenge lethal injection procedures under the Eighth Amendment.