The White House is criticizing Oklahoma's botched execution of Clayton Lockett, who appeared to be in pain and struggling to sit up minutes after he was pronounced unconscious.
Press Secretary Jay Carney said that while he has not discussed the case with President Barack Obama, anyone would agree Tuesday's lethal injection was not humane.
"He has long said that while the evidence suggests that the death penalty does little to deter crime, he believes there are some crimes that are so heinous that the death penalty is merited," Carney said.
"In this case, or these cases, the crimes are indisputably horrific and heinous. 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. And I think everyone would recognize that this case fell short of that standard."
Lockett's execution was halted by prison officials who said an intravenous line blew, but he died afterward of a massive heart attack.
A second execution scheduled for that night was postponed for at least two weeks while state officials conduct a review.
It was the first execution using Oklahoma's new three-drug protocol, which defense lawyers have denounced as experimental. Lockett also fought unsuccessfully to force the state to reveal where it obtained the chemical.
Lockett's aunt, Deanna Parker, told NBC News that she agreed with the White House's characterization of her nephew's death.
"I wish they would have spoken up before all this," she said.