Since capital punishment was reinstated three decades ago, nearly 900 of more than 1,055 U.S. executions have been carried out by lethal injection. But what was seen as a more humane alternative to the gas chamber, electric chair, firing squad or gallows now faces serious challenges.
The execution in Ohio last May of double-murderer Joseph Clark is a stark example of why America is taking a harder look at lethal injection.
Although Ohio had carried out 20 lethal injections without incident, prison officials encountered serious problems in executing Clark, a long-time intravenous drug user convicted of killing a service station attendant and a convenience store clerk. Reporters who witnessed the execution said Clark, 57, raised his head off the gurney and said repeatedly, "It don't work. It don't work." Prison officials closed the viewing curtain as they struggled to find a vein to inject the deadly chemicals. The procedure took almost 90 minutes.
Sparring over lethal injection will resume in courts and legislatures this year as authorities grapple with tough questions about how much pain the condemned feel as they die and what role, if any, medical professionals should play in executions.
The battle over lethal injection is the latest strand in a long-running debate over the ultimate punishment. The United States is among a handful of industrialized countries that sanction capital punishment. China, a totalitarian state, remains the leader, executing thousands of prisoners annually.
Read the full analysis Lethal Injection on Trial, Already on Hold in 12 States, the Death Penalty Faces Further Attacks in Courts and Legislatures this Year
on the Pew Research Center Web site.