Attorneys for a condemned murderer Monday asked a federal judge to stop the state from executing him until it is determined if Georgia's stock of a sedative used in the first stage of lethal injection is no longer potent.

Roy Willard Blankenship’s lawyers say if  the state’s stock of sodium thiopental, a sedative, has expired it’s potency will be weak and Blankenship could suffer excruciating pain when the second and third drugs are administered.

The state’s lawyer countered that there was no reason for the federal court to step in because there is no longer an execution date hovering over Blankenship.

Blankenship was to have been executed last Wednesday for raping and murdering 78-year-old Sarah Mims Bowen after breaking into her Savannah apartment on March 2, 1978.

Blankenship testified at trial that he climbed up to Bowen’s second story porch and broke in to steal a car, but someone else was in the apartment and that person raped and murdered the elderly woman. His lawyers say scrapings taken from underneath Bowen's torn fingernails, for example, revealed blood antigens that matched neither Bowen's nor Blankenship's blood type, the lawyers say.

A Savannah judge ordered the Georgia Bureau of Investigation to determine if DNA evidence taken from her body was still viable for testing. When the GBI said it was, the state Board of Pardons and Paroles delayed the execution. GBI spokesman John Bankhead said Monday there were no results yet on the DNA test and it was not known when the test would be completed.

U.S. District Judge Timothy Batten said he would have an answer by Tuesday.

In the meanwhile, Blankenship’s lawyers began fighting on another front: whether the state’s stock of sodium thiopental has expired. His lawyers say if  it’s potency will be weak Blankenship could suffer excruciating pain when the second and third drugs are administered. “The execution would be unconstitutional,” attorney Patrick Mulvaney argued.

The second drug – pancuronium bromide -- paralyzes and makes it impossible to detect if the condemned inmates suffers when the final one, potassium chloride, is sent into his veins.

“It’s only sodium thiopental that separates a legal execution from an unconstitutional one,” Mulvaney said.

Assistant Attorney General Tina Piper countered that there was no “imminent threat” of execution so there was no need for a temporary restraining order to stop it.

While DNA testing was the reason for stopping the execution, Blakenship’s lawyers are focusing on problems in Georgia and other states with aging supplies, or no supply at all, of sodium thiopental.

Several states, including Georgia, have had to get lethal injection drugs from England because of a shortage here, and executions have had to be delayed.

According to the suit, vials of sodium thiopental in the state’s stock were in vials labeled “Link Pharmaceuticals.”

“Link Pharmaceuticals does not exist,” Mulvaney said in the hearing.

Link was bought by another British company, Archimedes Pharma Limited, and Link Pharmaceuticals has not been on a label since May 2007.  If the labeling is accurate, the drugs in those vials would expire this coming May because the drug is good for only four years, Blankenship’s lawyer argued.

University of Georgia pharmacy professor Randall Tackett said in an affidavit filed with the suit that use of an expired sedative would create an “extremely high risk … the individual being executed [would] experience excruciating pain due to inadequate sedation."

Georgia has executed 48 men since 1983 – 24 by electrocution and 24 by lethal injection. One man, Emanuel Hammond, has been executed this year.