A federal judge heard arguments Tuesday from five death row inmates who say the state of Mississippi should halt executions until the U.S. Supreme Court rules on the constitutionality of lethal injection procedures.

U.S. District Judge W. Allen Pepper said he had more questions and would issue a ruling later, but did not specify when he would announce his decision.

One of the inmates involved in the case is Earl Wesley Berry, who is scheduled to die by lethal injection on Oct. 30 for a 1987 murder of Mary Bounds. Bounds was beaten to death after leaving her weekly church choir practice, and her body was found just off a Chickasaw County road near Houston, Miss.

Berry is the only one of the five with a pending execution date. The other four have appeals ongoing in the federal courts, according to the attorney general’s office.

Jim Craig, one of the attorneys for the inmates, argued there are no uniform standards for administering the drugs used in lethal injections, creating “a grave and substantial risk that plaintiffs will be conscious throughout the execution process and, as a result, will experience an excruciatingly painful and protracted death.”

Pepper said he wants to know more about the lethal cocktail and the training of the personnel who administer the drugs.

If Pepper decides Berry’s execution can go on as scheduled, the inmates’ attorneys will likely appeal the ruling to the 5th U.S. Court of Appeals.

In documents filed Friday, Assistant Attorney General Marvin White Jr. said Berry waited for more than five years, until his execution is imminent, to file a challenge to the execution procedure used in Mississippi.

“The method of execution used by the State of Mississippi has been in place for the entire 19 years that petitioner has been on death row,” White wrote in court papers. “He cannot contend that he was unaware of the method of execution during these 19 years.”