The Missouri Supreme Court has declined to set execution dates for six condemned killers, saying doing so is "premature" until the courts decide if Missouri's new execution method passes constitutional muster.
Missouri Attorney General Chris Koster in May asked the court to set the execution dates. That was the same month the Missouri Department of Corrections adopted a new execution protocol that uses a single drug, propofol.
Propofol has never previously been used as an execution drug, and a lawsuit filed by a death row inmate claims its use could violate the constitutional guarantee against cruel and unusual punishment.
The Supreme Court ruling was announced Tuesday.
Missouri has executed just two men since 2005 as courts have weighed constitutional challenges to the death penalty. Forty-six men are on death row.