TALLAHASSEE (AP) – Lawyers for a Florida death row inmate scheduled to be executed later this month will make their case to the state’s highest court on Thursday.

They plan to argue that John Errol Ferguson, 64, should be spared because Gov. Rick Scott denied him clemency based on an incomplete 25-year-old investigation.

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Ferguson is tentatively set for execution on Oct. 16 for murdering eight people in South Florida. The first six victims died in 1977 in a drug-related, execution-style mass killing in Carol City. Ferguson also was convicted of killing two Hialeah teenagers on their way to a church meeting in 1978.

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After Scott signed a death warrant he put the execution on temporary hold pending a psychiatric review to determine whether Ferguson is insane.

His lawyers contend clemency investigators never interviewed Ferguson because he was incompetent.

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