By Heide Brandes
OKLAHOMA CITY, April 23 (Reuters) - The Oklahoma Supreme Court lifted a stay of execution on Wednesday for two murderers, put in place due to concerns over secrecy surrounding lethal injection drugs, clearing the way for them to be put to death next week.
The court said their records indicate that the inmates have been provided with the identity and dosages of the drugs for the lethal injections and there were no pending secrecy concerns that would merit a further stay.
"The stay of execution entered by this Court on April 21, 2014, is hereby dissolved," it said.
The decision came a few hours after a member of the House of Representatives said he would start proceedings that could have led to impeachment proceedings in the state's legislature for court members.
The two inmates, Clayton Lockett and Charles Warner, had been scheduled to be executed in March but had the death sentences put on hold after lower courts ruled that the state needed to provide more information on the drugs.
"It's not even known whether the lethal injection drugs to be used were obtained legally, and nothing is known about their source, purity, or efficacy, among other questions," said Seth Day, an attorney for Lockett and Warner.
Lockett was sentenced to death for the 1999 murder of 19-year-old Stephanie Nieman. Warner was convicted of the 1997 rape and murder of 11-month-old Adriana Waller.
Several states have been scrambling to find new suppliers and chemical combinations after drug makers, mostly in Europe, imposed sales bans because they objected to having medications made for other purposes being used in lethal injections.
Attorneys for death row inmates have argued that the drugs used in Oklahoma and other states could cause unnecessarily painful deaths, which would amount to cruel and unusual punishment in violation of the U.S. Constitution (Editing by Ian Simpson; Editing by Michael Perry)