Published: Jul 26, 2011 3:17 AM EDT
Updated: Jul 26, 2011 2:19 AM EDT

TALLAHASSEE, Fla. (AP) - The Florida Supreme Court has stayed convicted killer Manuel Valle's execution so a judge can hear arguments over the use of a new lethal injection drug.

The justices on Monday delayed the execution for a month, from Aug. 2 until Sept. 1, absent further order of the high court.

Valle was convicted of killing a Coral Gables police officer 33 years ago.

Florida and several other states have been forced to seek alternatives to sodium thiopental, part of a three-drug cocktail used in lethal injections.

That's because the sedative's sole U.S. manufacturer has stopped making it.

Florida last month adopted a new procedure that substitutes pentobarbital.

Valle's lawyers contend the new drug's use will subject him to "substantial risk of harm."

Valle's family lives in southwest Florida.

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