In a padlocked refrigerator behind San Quentin State Prison's death chamber, 12 grams of scarce sodium thiopental is available to carry out up to four executions.
How the California Department of Corrections and Rehabilitation acquired the drug is both a mystery and an apparent impediment to its use.
Legal analysts and human rights advocates contend that the state must have gotten the drug from a foreign producer because all stocks made by Hospira Inc. of Lake Forest, Ill., have expired, or will soon expire, and the drug's sole U.S. manufacturer can't make more, reportedly because of a raw-material supply issue.
In a legal filing to a federal judge reviewing the state's new lethal injection procedures, the office of Atty. Gen. Jerry Brown disclosed last month that it had obtained 12 grams of sodium thiopental with a 2014 expiration date.
Asked where the state found the drug, corrections spokeswoman Terry Thornton said: "I'm not at liberty to say."
The state's previous supply of sodium thiopental, which Hospira manufactures as Pentothal, expired at the end of September.
The exceeded shelf life was among the reasons U.S. District Judge Jeremy Fogel called off the scheduled Sept. 30 execution of rapist-murderer Albert Greenwood Brown, which would have been the first death sentence carried out in this state in nearly five years.
Fogel, based in San Jose, has blocked executions since February 2006, when he expressed concern that state executioners might not have let the sodium thiopental fully anesthetize some inmates before they were injected with the second and third drugs of the lethal series, which respectively paralyzed them and stopped their hearts. Unless the powerful barbiturate has rendered an inmate unconscious, he or she could be exposed to severe pain, in violation of the 8th Amendment's prohibition on cruel and unusual punishment, Fogel has said.
"The problems Judge Fogel found are the reasons why the court and the public are entitled to know whether the state is using sodium thiopental that will work in the way it is supposed to work," said Elisabeth Semel, a UC Berkeley law professor and director of the school's Death Penalty Clinic.
"If one is working with an FDA-approved drug, we know how it is supposed to be mixed and administered," she said. "If it comes from a foreign source, then we don't have that information, and the risk of serious harm escalates."
A 2008 U.S. Supreme Court ruling in a challenge brought by two Kentucky death row inmates found the lethal injection procedures used in that state to be constitutional. That decision, Baze vs. Rees, endorsed procedures similar to those used in all 35 death penalty states but required state officials to conduct executions in a "transparent" manner, something that California may be failing to do in declining to reveal the source of its sodium thiopental, said Semel, who opposes capital punishment.
Those in favor of resuming executions say the arguments are unpersuasive.
"I don't think there is a serious claim that Europe's standards are so much lower than ours that we should presume European drugs are substandard," said Kent Scheidegger, legal director for the Criminal Justice Legal Foundation in Sacramento. "It is absurd to claim that a drug used for the specific purpose of killing the inmate has to be approved through a process designed to ensure it is safe."
Pentothal is designed for use in surgical procedures and "is not indicated for capital punishment," said Hospira spokesman Dan Rosenberg, reiterating a warning sent to corrections departments around the nation earlier this year.
Product literature warns of potential respiratory complications and says Pentothal should not be used on anyone without "suitable veins for intravenous administration." Ohio's governor last year had to call off the attempted execution of murderer Romell Broom when corrections workers failed for more than two hours to find a vein strong enough to hold the IV shunt.
California has executed 13 inmates since capital punishment was reinstated in 1976, two by lethal gas and 11 by lethal injection. No executions have been carried out since January 2006 because of reviews and procedural revisions ordered by Fogel. The death row population has since swelled to 713 — the nation's largest by far.
Only seven of those condemned prisoners have exhausted all of their appeals and are eligible for execution, said Christine Gasparac, spokeswoman for the attorney general's office.
Gasparac declined to say whether state law prohibits the import or use of lethal-injection drugs manufactured abroad and lacking U.S. Food and Drug Administration approval.