Lethal injection has become a prominent method of execution because other methods, including electrocution, could more easily be seen as conflicting with the Eighth Amendment's ban on “cruel and unusual” punishment, Ian Steadman writes in the New Statesman. However, critics of lethal injection argue that the procedure causes “extreme and unnecessary pain,” that the combination of drugs camouflage this pain and that the method itself is “cruel and unusual,” according to the Death Penalty Information Center.

The most common method of execution since 1976, lethal injection typically has involved three specific drugs which when combined, induce death by paralyzing the muscles and stopping the heart. But the pipeline for the combination normally used in the procedure dried up across the country after European producers and ultimately the European Union restricted the sale of drugs for use in executions, according to the Post and Nature.

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