Oklahoma’s attorney general said Friday he will not seek any executions until 2016 while investigators figure out how the wrong drug was used in an inmate’s January execution.

Alongside the announcement, Attorney General Scott Pruitt (R) filed a request Friday to suspend proceedings in a lawsuit over Oklahoma’s lethal injection laws.

In it, Pruitt says he will not request any executions until 150 days after the investigation is done and made public and prison officials say they are able to follow Oklahoma’s execution protocol. The filing (available here) was a joint request made by Pruitt as well as lawyers representing those death row inmates in the lawsuit.

The hold on Oklahoma’s executions is the latest twist after a year of battles and surprising developments over capital punishment in the state. Last month, hours before the scheduled execution of Richard Glossip, a state appeals court temporarily halted it to give judges time to consider his appeals. Two weeks later, just hours before Glossip’s rescheduled execution, Oklahoma Gov. Mary Fallin (R) called it off.

Prison officials had told Fallin that instead of receiving potassium chloride — the last drug used in Oklahoma’s lethal injection procedure — they received potassium acetate. Then, last week, Fallin said authorities discovered potassium acetate was used in the execution in January of Charles Warner.

Fallin stressed in a written statement that a doctor and pharmacist working with prison officials said the two drugs are medically interchangeable since potassium is the active ingredient that stops the heart. But the confusion has added to controversy and questions over the exact protocol and drugs used in Oklahoma’s executions.

And it comes on the heels of Oklahoma’s widely publicized botched execution of Clayton Lockett last year.

Lockett’s execution was halted 20 minutes in because of vein problems, but he began writhing on the gurney and was declared dead 43 minutes after the execution began due to a heart attack.

Glossip’s case and attempts to execute him have generated widespread attention and controversy. Post Nation’s Mark Berman previously summed up his case on Sept. 16 when it was dramatically halted:

The case focused on the killing of a motel owner named Barry Van Treese. In 1997, Van Treese was beaten to death with a baseball bat. Glossip, who worked for Van Treese, was found guilty of paying another motel worker to kill him. Justin Sneed, who confessed to killing Van Treese, testified against Glossip, and he was sentenced to life in prison without parole while Glossip received a death sentence.
Glossip, 52, was convicted of murder and twice sentenced to death. He was first sentenced in 1998, but that sentence was overturned due to what a state court deemed ineffective legal counsel, and he was sentenced again in 2004.
But Glossip’s attorneys argue that executing him based on Sneed’s testimony “risks a wrongful execution.” They also submitted an affidavit from a man who said that while in an Oklahoma state prison, he heard Sneed say that Glossip hadn’t done anything.
U.S. Sen. Tom Coburn (R-Okla.), former University of Oklahoma football coach Barry Switzer and Barry Scheck, co-founder of the Innocence Project, signed a letter published last week that called on Fallin to “prevent a deadly mistake” and stay the execution.
“We also don’t know for sure whether Richard Glossip is innocent or guilty,” they wrote in the letter. “That is precisely the problem.”
Two other prominent voices opposing the execution were Sister Helen Prejean, a prominent death penalty opponent, and Susan Sarandon, an activist and actor who won an Oscar for her portrayal of Prejean in the movie “Dead Man Walking.” More than 236,000 people had signed a petition on MoveOn.org from Prejean and Sarandon asking Fallin to delay the execution due to “a breathtaking lack of evidence” in the case.