The Tennessee Supreme Court has rescheduled the execution of murderer Billy Ray Irick.

Irick, who raped and killed a 7-year-old Knoxville girl he had been baby-sitting in 1985, had been scheduled to die by lethal injection Jan. 15 in a wave of executions Tennessee is seeking to carry out.

But the Supreme Court rescheduled the execution for Oct. 7, 2014, because of new legal challenges to the way Tennessee plans to put the condemned to death.

Tennessee's executions have been been on hold for at least two years because a key lethal injection drug, sodium thiopental, became unavailable.

It wasn't until September of this year that the state settled on a replacement, the anasthetic pentobarbital, often used in animal euthanasia.

State officials, thinking the drug switch cleared the way to begin executions, have asked the Supreme Court for dates to execute at least 11 inmates.

So far, it has only scheduled Irick and Nickolus Johnson, who is scheduled to be put to death April 22 for killing a Bristol police officer in 2004.

But the court on Tuesday said that new legal challenges questioning the use of pentobarbital must be answered before it can be used in an execution.

"Mr. Irick is correct that currently, there is no controlling law in Tennessee on the constitutionality of the use of the single drug, Pentobarbital, to execute a death row inmate," the court said in its order postponing Irick's execution.

The legal challenge is being fought by attorneys for at least 10 of the condemned the state is looking to execute.

"We are grateful for the Tennessee Supreme Court's order.

All of the parties have agreed to an expedited schedule to litigate the serious questions which surround the new lethal injection protocol," said Kelley Henry, who supervises capital punishment defense cases with the Federal Public Defender's Office in Nashville and represents several of those the state is looking to execute. "Our Supreme Court recognized that these are important constitutional issues which have never been litigated in this State. We look forward to the opportunity to have our day in Court."