OKLAHOMA CITY — Oklahoma Gov. Mary Fallin called Wednesday for an independent review of the state’s execution protocols after a botched procedure that the White House said fell short of the humane standards required.

Fallin said Clayton Lockett, who had an apparent heart attack 43 minutes after his execution began, had his day in court and the legal process worked.

“I believe the death penalty is an appropriate response and punishment to those who commit heinous crimes against their fellow men and women,” Fallin said. “However, I also believe the state needs to be certain of its protocols and its procedures for executions and that they work.”

Oklahoma Attorney General Scott Pruitt says he wants his office involved in the investigation.

Pruitt said Wednesday he plans to assign investigators from his office to work on the investigation that has been ordered by Gov. Mary Fallin.

Fallin said the review will be conducted by a member of her Cabinet.

Pruitt’s office was responsible for prosecuting the inmate who died, went to court to keep secret the source of the drugs and worked on the state’s execution protocol.

A spokesman for Fallin didn’t immediately comment on Pruitt’s plans.

Fallin said the review will focus on Lockett’s cause of death, noting that the Oklahoma State Medical Examiner has authorized an independent pathologist to make that determination. The review will also look at whether the department followed the current protocol correctly and will also include recommendations for future executions.

The governor also said a stay for Charles Warner, who had been scheduled to die two hours after Lockett, is in place until May 13. She said Warner’s execution will be further delayed if the independent review is not completed by then. Warner’s attorney immediate raised objections to the investigation being led by a member of Fallin’s Cabinet.

Lockett, 38, had been declared unconscious 10 minutes after the first of three drugs in the state’s new lethal injection combination was administered Tuesday evening. Three minutes later, he began breathing heavily, clenching his teeth and straining to lift his head. Officials later blamed a ruptured vein for the problems with the execution, which are likely to fuel more debate about the ability of states to administer lethal injections that meet the U.S. Constitution’s requirement they be neither cruel nor unusual punishment.

The blinds eventually were lowered to prevent those in the viewing gallery from watching what was happening in the death chamber, and the state’s top prison official later called a halt to the proceedings. Lockett died of a heart attack shortly thereafter, the Department of Corrections said.

In Washington, White House spokesman Jay Carney said that President Barack Obama believes that evidence suggests the death penalty does little to deter crime, but that some crimes are so heinous that the death penalty is merited.

“But it’s also the case that we have a fundamental standard in this country that even when the death penalty is justified, it must be carried out humanely,” Carney said. “Everyone would recognize this case fell short of this standard.”

Questions about execution procedures have drawn renewed attention from defense attorneys and death penalty opponents in recent months, as several states scrambled to find new sources of execution drugs because drugmakers that oppose capital punishment — many based in Europe — have stopped selling to U.S. prisons and corrections departments.

Defense attorneys have unsuccessfully challenged several states’ policies of shielding the identities of the source of their execution drugs. Missouri and Texas, like Oklahoma, have both refused to reveal their sources and both of those states have carried out executions with their new supplies.

Fallin said Oklahoma Department of Public Safety Commissioner Michael Thompson would lead the review of the lethal injection protocol. Thompson is head of the state police and Fallin’s Secretary of Safety and Security, a member of her cabinet.

Warner’s attorney, Madeline Cohen, said she has concerns about that.

“I don’t consider that to be an independent investigation,” Cohen said.

The medical examiner’s office, which said earlier Wednesday that the autopsy had begun, later said only the toxicology portion of the autopsy had been started and that the surgical portion will be conducted by an independent pathologist.

Medical examiner’s spokeswoman Amy Elliott said the autopsy on Lockett would include an examination of the injection sites on his arms and a toxicology report to determine what drugs were in his system. Elliott said and it could take two to four months to complete the toxicology report.

Tuesday was the first time Oklahoma used the sedative midazolam as the first element in its execution drug combination. Other states have used it before; Florida administers 500 milligrams of midazolam as part of its three-drug combination. Oklahoma used 100 milligrams of that drug.

The execution began at 6:23 p.m., when officials began administering the midazolam. A doctor declared Lockett to be unconscious at 6:33 p.m.

Once an inmate is declared unconscious, the state’s execution protocol calls for the second drug, a paralytic, to be administered. The third drug in the protocol is potassium chloride, which stops the heart. Robert Patton, the department’s director, said the second and third drugs were being administered when a problem was noticed. He said it’s unclear how much of the drugs made it into the inmate’s system.

Lockett began writhing at 6:36. At 6:39, a doctor lifted the sheet covering him to examine the injection site.

“There was some concern at that time that the drugs were not having that (desired) effect, and the doctor observed the line at that time and determined the line had blown,” Patton said at a news conference afterward, referring to Lockett’s vein rupturing.

After an official lowered the blinds, Patton made a series of phone calls before calling a halt to the execution.

Lockett was declared dead at 7:06 p.m.

In Ohio, the January execution of an inmate who made snorting and gasping sounds led to a civil rights lawsuit by his family and calls for a moratorium. That execution also used the drug midazolam, but in a lower dosage than Oklahoma used and as part of a two-drug combination. The state has stood by the execution but said Monday that it’s boosting the dosages of its lethal injection drugs.

A four-time felon, Lockett was convicted of shooting 19-year-old Stephanie Neiman and watching as two accomplices buried her alive in rural Kay County in 1999. Neiman and a friend had interrupted the men as they robbed a home.

Lockett and Warner had sued the state for refusing to disclose details about the execution drugs, including where Oklahoma obtained them. The case, filed as a civil matter, placed Oklahoma’s two highest courts at odds. The state Supreme Court later dismissed the inmates’ claim that they were entitled to know the source of the drugs.