On Tuesday, Clayton Lockett died of a heart attack more than an hour after his botched lethal injection began. Things went so wrong that the state of Oklahoma’s second scheduled execution for that night was stayed for 14 days.

A notable thing about Lockett’s slow demise is that it came as no great surprise to some. As reported recently in The Washington Post, lethal injection’s tidiness in death is mostly show. Even when it goes smoothly, the individual may be suffering great pain. If the death penalty were really about killing the criminal in the swiftest, most humane method possible, we would probably use a guillotine. But that would be awfully uncomfortable for the witnesses. A person who falls gently asleep can make us all feel satisfied in our superior humanity – a rapist, murderer,or torturer, is getting a decent death, the way an old pet dog might. Someone who struggles painfully for 45 minutes after being given a new drug cocktail, as Lockett did, feels different. Lethal injection is not unique in its propensity for failure. A recent Boston Globe story describes research that shows a long history of botched American executions of all varieties. However, there is a 3 percent failure rate for execution by hanging, electrocution, gas, and firing squad. Lethal injections are botched 7 percent of the time.

This is not to say that Lockett, who if he was as guilty as the verdict said, didn’t "deserve" to suffer. Lockett shot a 19-year-old woman and then stood by while his comrades buried her alive. To think too long about that is to feel queasy horror. But is that the point when we’re discussing the right or wrongs of a government policy of legal killing? Wars big and small abroad should not be about, "Well, at least Saddam and those two nasty sons of his are dead!" Hundreds of thousands of Iraqis are dead – that’s the important part about the immorality of the war in Iraq. Drones have undoubtedly killed some nasty people as well – ones who intended to commit violence in the name of their political cause. Does that make drones okay? Does that make the psychological torture of fearing them 24/7 okay? Does one honest-to-God al-Qaeda member killed – or even 50 – bring back any of the 200 kids who died? It does not.

Worse even than executing undeniably bad people for the vague, dubious "principle" of deterring other bad people from committing murder is the reality that innocent people do end up on death row – and some of them are executed. A recent study in Proceedings of the National Academy of Sciences suggested that "a conservative estimate" of innocent people sentenced to death in the United State is 4.1 percent. Or, as conservative Ron Keine recently wrote in The Daily Caller, "I can tell you firsthand that the death penalty runs an inherent and undeniable risk of killing innocent people. In fact, I am one of over 140 individuals who have been wrongly convicted and sentenced to death." Keine was convicted on shoddy eyewitness testimony and little else back in 1974. As he puts it, they were just starting to ask what he wanted for his last meal when the real killer confessed. Now working for Witness to Innocence, Keine offers financial, philosophical, and religious objections to the death penalty in his piece. However, his most compelling argument is simply that the legal system is not good enough to be trusted with life or death matters. Not now – likely not ever.

Since the death penalty was brought back after a four-year moratorium in the 1970s, eight additional states of the 39 that allowed it in 1972 have banned capital punishment over fears that the policy as it exists is irredeemably flawed. Since the 17th century, the United States (and the Colonies) has put 17,000 people to death. Most everyone who supports the death penalty today would admit that, say, Giles Cory shouldn’t have been crushed to death by stones for refusing to enter a guilty or innocent plea for the charge of witchcraft in 1692. But then, Cameron Todd Willingham, a man most people now agree was wrongly sent to death in 2004, also refused to plead guilty to triple murder to save himself. Based on a jailhouse informant, dodgy arson science, and the fact that some witnesses didn’t think he was sufficiently distraught, Willingham was convicted of setting the fire that killed his three kids in 1991. Yet when he was offered the deal that would have given him life in prison, Willingham said, "I ain’t gonna plead to something I didn’t do, especially killing my own kids." There’s more than a little Giles Cory there, some 300 years later.

Liberals often point to the rest of the Western world having moved past the death penalty. Indeed, you’d think the "shining city on a hill" conservative crowd would feel uncomfortable being in the same league with China, Saudi Arabia, and Iran when it comes to killing their own citizens.

More to the point, conservatives and Republicans critique every aspect of clunky, messy government intervention – from the DMV, to ObamaCare, to occupational licensing. But when it comes to such life and death matters as wars and executions, they carry a bizarre, easy confidence that government policies are near-flawless.

Botched or not, innocent or not, successful deterrent or not, the death penalty is just another can’t-take-it-back government policy performed by people and institutions that there is every reason in the world to distrust.

Like supporting war (both boots on the ground and robotic), being for the death penalty as it exists is to accept a certain number of innocent casualties and a certain brutality of methods. And killers always have their reasons to take life, be it psychotic pleasure, hot rage or a cold, clinical sense that justice must be done.

Lucy Steigerwald is a contributing editor for Antiwar.com and a columnist for VICE.com. She previously worked as an Associate Editor for Reason magazine. She is most angry about police, prisons, and wars. Steigerwald blogs at www.thestagblog.com.