Supreme Court won't hear Tennessee death row inmates' appeal

The U.S. Supreme Court won't consider an appeal that could have delayed an upcoming Tennessee execution.

The appeal involves Tennessee's midazolam-based lethal injection combination. Inmates claim in a lawsuit that the method causes excruciating pain.

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The appeal doesn't challenge lethal injection directly. Instead it challenges Tennessee secrecy laws surrounding the procurement of execution drugs. Inmates argue the laws prevented them from proving a more humane drug is available.

Justice Sonia Sotomayor agrees. In her dissent on Monday, she says the requirement that prisoners challenging one method of execution prove there is a better method available is "fundamentally wrong." She adds that state secrecy laws compound the injustice.

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Don Johnson is scheduled to be executed Thursday for the 1984 murder of his wife, Connie Johnson.