Teresa Lewis is sitting on death row. Convicted of plotting to have both her husband and stepson murdered so that she could cash in their life insurance policies, Lewis is scheduled to be put to death by lethal injection on Thursday. Governor of Virginia Robert McDonnell, the only individual with the power to grant clemency to death row inmates in his state, has said that he will not intervene. Lewis' attorney, James E. Rocap, III, filed a Petition for Writ of Certiorari and Application for Staywith the United States Supreme Court, but the Court declined to review the case. It appears Lewis will become the first woman in nearly a century to be executed in Virginia.

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Killing a patient by injecting drugs meant to ensure near-immediate death has been talked about as a concept for well over one hundred years, but wasn't adopted by a state until 1977 when the Oklahoma legislature chose lethal injection as a replacement for the electric chair. Jay Chapman, then the state's medical examiner, had proposed an intravenous drip to execute death row inmates earlier that year, arguing it would be a less painful method than existing practices.

Injection1.jpgWhile the practice varies widely from state to state -- and country to country -- the saline drip, known as Chapman's Protocol, serves as the base for all lethal injections carried out today.

In the United States, the patient is strapped onto a table located within a secure execution chamber where intravenous drips are placed in each arm. While only one drip is necessary, the second acts as a fail-safe. Long tubes connected to the needles pass out of the chamber and into a second room where the executioner or executioners, most often chosen by the prison's warden, await further orders. In the second room, they remain out of sight of anyone allowed to watch the procedure. In some states, the warden carries out the execution; in others, the executioner is never identified.

In Virginia, inmates sentenced to death are allowed to choose between lethal injection and electrocution. Lewis declined to choose, her attorney told me. "By statute, the default method of execution is lethal injection.

At the warden's signal, between one and three chemicals are injected into the IVs, separated by a saline solution used to ensure that the chemicals do not mix. The first, sodium thiopental, is a barbiturate that puts the patient into a deep sleep. At the dose, between two and five grams, most often used in lethal injection cases, unconsciousness is induced in about 10 seconds. The second chemical, pancuronium bromide, acts as a paralyzing agent that freezes the diaphragm and lungs so that the patient stops breathing. As the patient is often legally dead after the first two injections, the third, potassium chloride, is only administered in some states. Potassium chloride stops the heart.

Ohio and Washington state use only the first chemical, sodium thiopental, but in such a large dose that the patient, after falling into unconsciousness, experiences the widening of blood vessels to such an extreme that blood pressure drops to a lethal level.

In Virginia, all three of the chemicals are used, though officials will not reveal their exact make-up. Consistent with most other states, "the first chemical stops brain activity, the second causes respiration to cease, and the third stops the heart," according to Richard C. Dieter, executive director of the Death Penalty Information Center in Washington, D.C. 

Images: 1. Andres Rueda/Flickr; 2. Blatant News/Flickr.

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