TALLAHASSEE - Condemned killer Bennie Demps lost an appeal to the state Supreme Court on Monday, two days before the state plans to execute him for the 1976 murder of another inmate.

The high court rejected Demps' appeal in an unsigned unanimous ruling. One of Demps' lawyers immediately filed a long-shot petition asking the U.S. Supreme Court to delay the execution.

The state Supreme Court ruled a few hours after hearing oral arguments during which Demps' lawyer told the justices that a 1976 memo could have kept Demps from being convicted and condemned.

Gainesville lawyer William Salmon called the document ``incredibly explosive.''

A lawyer for the state, Curtis French, told the justices that the memo ``amounts to a hill of beans.''

Demps, 49, is scheduled to die by lethal injection at 6 p.m. Wednesday for the 1976 murder of Alfred Sturgis.

Guards at Florida State Prison found Sturgis, 23, who was serving a life sentence for second-degree murder, bleeding in his cell.

At Demps' trial, a prison guard testified that Sturgis told him that Demps and another inmate held him down while a third stabbed him. Demps was sentenced to death. The other two were sentenced to life in prison.

In Demps' appeal, Salmon argued that an internal memo written to the head of the state Department of Corrections a day after Sturgis' murder mentioned only one assailant.

The memo could have been used to show that Demps wasn't involved in the attack at all, Salmon argued Monday.

Salmon found the memo when he handled Demps' case a couple of years ago. He said it should be considered new evidence.

French argued that the memo has never been withheld from Demps' attorneys and has been around, and available, for years.

Demps was originally scheduled to be executed last Wednesday. But the state Supreme Court agreed to delay the execution until this Wednesday to give Demps' attorneys more time.

Demps was first sent to death row for the 1971 murders of R.N. Brinkworth and Celia Puhlick, who were fatally shot in a Lake County citrus grove.

The victims were inspecting land for sale in Winter Garden when they happened upon Demps, who had fled to the grove with a stolen safe. Puhlick's husband, Nicholas, was wounded.

Those death sentences were reduced to life prison terms when the U.S. Supreme Court halted capital punishment in 1972 because it was imposed arbitrarily.

Before the end of the year, Florida became the first state in the nation to write a new death penalty law. In 1976, the nation's high court upheld Florida's death penalty statute.

Sturgis was murdered a few months later.