By Heide Brandes
OKLAHOMA CITY (Reuters) - The Oklahoma House of Representatives passed a bill on Tuesday allowing nitrogen gas as a means of execution, a measure that comes after a troubled lethal injection last year raised questions about how the state executes inmates.
The bill, which passed by a vote of 85 to 10, authorizes nitrogen gas as an alternative form of execution if lethal injection is found to be unconstitutional by the U.S. Supreme Court.
The process, which would require an inmate to be in a sealed chamber or wear a special mask, would slowly replace oxygen with nitrogen, lawmakers said.
State Representative Mike Christian, a Republican who authored the bill, has said the process would be painless for inmates and affordable for Oklahoma.
"Nitrogen hypoxia is a better way. It's a more humane way. I believe the use of nitrogen hypoxia will be the thing of the future once it’s passed in Oklahoma," Christian said.
In January, the U.S. Supreme Court agreed to temporarily block the execution of three Oklahoma inmates who are challenging the state's lethal injection procedure.
Oklahoma's three-drug process has been under scrutiny since the flawed April 2014 execution of convicted murderer Clayton Lockett. He could be seen twisting on the gurney after death chamber staff failed to place the IV properly.
The execution was halted and Lockett died about 45 minutes after it started due to a buildup of lethal injection chemicals in his tissue. The state received wide criticism and the troubles prompted the White House to say it would re-examine death chamber protocols in the country.
The bill now moves to the Oklahoma Senate for consideration.
(Writing by Jon Herskovitz)