Warning: This report contains disturbing descriptions of executions.
Since lethal injection was first used in Texas in 1982, a very large proportion of executions in the United States have been carried out by this method.
The Death Penalty Information Center, a nonprofit think tank that does not take a position on capital punishment policy, says that over the past 50 years, out of a total of 1,683 executions, 64 cases have been linked to problems or failures in execution, including 51 cases of botched lethal injections.
The difficulty of carrying out the executions and protests against what some consider inhumane treatment have forced authorities to consider alternative methods of killing convicts. Getty Images.