JACKSON, Miss. (AP) — A challenge to lethal injection in Mississippi is on hold until the U.S. Supreme Court decides a Missouri case.

Trial had been scheduled Aug. 27. But Judge Henry Wingate ordered the delay Friday.

A lawyer for some of the Mississippi inmates had said trial would be a waste of time when the Supreme Court is likely to clarify the law.

Both cases hinge on whether an alternate execution method would reduce risk of needless suffering.

Mississippi inmates say the state should use the sedative pentobarbital. Prison officials have said they can’t obtain it.

In Missouri, Russell Bucklew says a gas chamber would be more humane than pentobarbital. He says a drug injection could rupture a tumor in his throat, causing him to choke on blood.