Published: Jun 12, 2014 12:06 PM EDT

TALLAHASSEE, Fla. (AP) - The Florida Supreme Court has dismissed an appeal to overturn the death sentence of John Ruthell Henry.
    
The convicted triple murderer has been on Florida's death row for 24 years and is scheduled for execution Wednesday night.
    
The 63-year-old Henry was convicted in Pasco County of fatally stabbing his wife Suzanne Henry. Gov. Rick Scott signed John Henry's death warrant for that murder.
    
He also was convicted in Hillsborough County of stabbing Suzanne Henry's five-year-old son near Plant City a short time later.
    
Henry pleaded no contest to second-degree murder for fatally stabbing another woman, Patricia Roddy, in 1976. He served less than eight years in prison and was released in 1983.
    
Henry's appeal attempted to stay the execution on the claim that he is intellectually disabled.

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