The U.S. Supreme Court Tuesday denied a petition to stop the execution of an Arizona death-row inmate. The execution by lethal injection is scheduled for 10 a.m. Wednesday at Florence.

Richard Dale Stokley's lawyers argued that he is entitled to a new hearing on sentencing evidence. They also said his constitutional rights are being violated because another man convicted in the case has been released after serving 20 years in prison.

The Supreme Court ruled without comment.

Prosecutors had argued that the Arizona Supreme Court adequately considered evidence on possible leniency for Stokley. Prosecutors defended the disparity in sentences by saying the other man negotiated a plea agreement.

Stokley and another man were convicted of murdering 13-year-olds Mandy Meyers and Mary Snyder in rural Cochise County in 1991.