(CNN) -- Last week in McAlester, Oklahoma, the blinds were raised in a small, white, antiseptic room, and two small groups of people watched as Clayton Lockett was strapped to a gurney. A doctor examined Lockett's body for usable veins and then oversaw the administration of an untested drug cocktail that was supposed to dispatch the convicted murderer quickly and quietly. Instead, the blinds were lowered as the execution turned into more than 40 minutes of grimacing, writhing, teeth grinding and frantic phone calls. Then Lockett's heart finally seized, stopped beating, and his breath left his body. This is how we kill our most serious criminals in the 21st century. Or at least try to. So if this is justice, let's make it real. Let's make it open to the highest form of public transparency and scrutiny: Live TV. Here's why.
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Richard Gabriel: Recent failed execution makes the case against death penalty
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The last public execution in the United States was in 1936, witnessed by 20,000 people
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Gabriel says he believes there is no humane way to kill another person
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We should be willing, he says, to live with the byproducts of our retribution
@placeholder's botched lethal injection marks new front in battle over executions