this article was written in 1995, very interesting.
Killing with kindness - capital punishment by nitrogen asphyxiation
Capital punishment needn't be cruel or unusual -- especially if you use nitrogen asphyxiation to put people to sleep.
LAST October, Judge Marilyn Hall Patel of the 9th U.S. District Court ruled that execution in California's gas chamber is a form of cruel and unusual punishment, the first ruling ever by a state or federal judge to invalidate a method of execution on Eighth Amendment grounds. She noted that the evidence showed that the condemned man might remain conscious for several minutes, experiencing the emotions of `anxiety, panic, terror,' as well as `exquisitely painful muscle spasms' and `intense visceral pain.'
On its face, Judge Patel's ruling applies only to the gas chamber, but every method of execution in current use involves toxic chemicals or physical trauma to induce death -- and every method can go awry. An ideal hanging snaps the condemned man's neck cleanly; a botched one either strangles him slowly or severs the head entirely from the body. A firing squad that misses its mark leaves the condemned man conscious as he bleeds to death. In the electric chair, according to eyewitness accounts, some condemned men have literally been cooked until their flesh was charred and loosened from the bone; some had sparks and flame emanating from their cranial-cap electrodes.
Besides society's concern for the condemned man's physical suffering, all of these methods implicitly require an executioner to inflict some degree of trauma upon the condemned. Concern for the executioner's conscience drives such customs as loading one of the guns for a firing squad with a blank cartridge, so that each member of the squad can imagine that his will be the non-lethal shot. And with lethal injection, the executioner's use of skills and procedures normally devoted to life-saving poses ethical questions for medical caregivers.
Given these defects, abolitionists will presumably press to have each of these methods declared `cruel and unusual.' The intended result of these efforts is to make the death penalty unconstitutional in practice, even if it remains constitutional in theory.
It is in fact possible to conceive of a method of execution that would cause neither pain nor physical trauma, require no medical procedure (other than pronouncing death), and use no hazardous chemicals. A case of accidental death suggests such a method.
Early in the Space Shuttle program, a worker at Kennedy Space Center walked into an external fuel tank (a vessel nearly as big inside as a Boeing 737) to inspect it. He was not aware that it had been purged with pure nitrogen gas to prevent oxygen in the air from corroding its interior. Since nitrogen is the major component of ordinary air, pure nitrogen has no distinctive feel, smell, or taste; the worker had no indication that anything was out of the ordinary. After walking a short distance into the tank, he lost consciousness and collapsed. A co-worker, not realizing that his collapse had an external cause, ran in to aid him and succumbed also. By the time other workers realized what was happening, the two men were dead.
More recently, a bizarre accident involving nitrogen killed two people in the Bay Area. They had stolen from a hospital a gas cylinder containing what they thought was laughing gas. However, the cylinder contained not the anaesthetic nitrous oxide but pure nitrogen. When the two men stopped their car to partake of their booty, the nitrogen gas displaced the air in the car, leaving them without oxygen. Had they had any indication of the problem, they could have saved their lives simply by opening the car doors.
These deaths were similar in cause to a relatively common drowning accident known as shallow-water blackout, mentioned specifically in certification classes for recreational scuba diving. When a person is skin diving (that is, without scuba gear), his bottom time is limited by how long he can hold his breath. Occasionally, a skin diver will attempt to lengthen the time he can stay under by hyperventilating before a dive. Unfortunately, this can lead to his losing consciousness underwater, sometimes only a few feet before reaching the surface.
THE connection between nitrogen asphyxiation and shallow-water blackout lies in human respiratory physiology. When you hold your breath, you begin to develop a powerful urge to breathe. This is caused not by the depletion of oxygen from your body, but by the buildup of carbon dioxide in your bloodstream, which changes the pH of the blood. The ambitious skin diver ``blows off' most of the carbon dioxide in his bloodstream when he hyperventilates; as a result, he notices the urge to breathe much later than he normally would, at a point when his blood oxygen is dangerously low. If his blood oxygen falls too low before he reaches the surface, he blacks out and drowns. Because the Kennedy Space Center workers continued to exhale carbon dioxide with each breath, neither of them noticed an unusual urge to breathe, even though they were completely deprived of oxygen.
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