Oklahoma Gov. Mary Fallin signed a bill into law Friday that allows the state to perform executions using nitrogen gas should lethal injection be ruled unconstitutional or become unavailable.
According to Fallin's office, nitrogen causes a quick loss of consciousness and then death from lack of oxygen. Research conducted by Americans.org found no record of nitrogen ever being used in an execution in the United States.
"The person will become unconscious within eight to 10 seconds and death a few minutes later. In other words, a humane, quick and painless death," said Rep. Mike Christian, one of the bill's authors.
Robert Dunham, executive director of the Death Penalty Information Center, told the Washington Post that the same "painless" argument has been used before to advance the use of lethal injections.
"The hasty manner in which this bill sped into law reflects the same lack of care with which Oklahoma has managed its execution process historically," he said.
Currently Oklahoma has put all executions on hold while the U.S. Supreme Court reviews its use of lethal injections. The state came under scrutiny last year when it took 43 minutes to kill convicted killer Clayton Lockett.
Fallin remains unwavering in her support for the death penalty.
"Oklahoma executes murderers whose crimes are especially heinous," Fallin said. "I support that policy, and I believe capital punishment must be performed effectively and without cruelty. The bill I signed today gives the state of Oklahoma another death penalty option that meets that standard."
The governor's office said the first choice for execution is lethal injection, followed by nitrogen gas, the electric chair and the firing squad.