A northern California judge has rejected the state's new protocol for lethal injections affecting death penalties.

Judge Fay D'Opal, a Marin County Superior Court official, said correction officials had failed to explain why the single injection method, used in some other states, was not considered in the new rules; the current standard is a three drug injection method. The new protocol was, therefore, ruled invalid and in violation of California law and legal requirements.

The legality of the revised procedures was challenged by a death row inmate Mitchell Sims, condemned for 1985 killings of three employees of a Domino's Pizza store. The last execution in California was Clarence Ray Allen, 76, in January, 2006, after which U.S District Judge Jeremy Fogel halted the handing down of lethal injections.

The Three Drug Formula:

The three drug formula as, it is popularly called, consists of administering three separate drugs, intravenously. The three drugs are administered in the following sequence:

1) Sodium thiopental - a short-acting barbiturate - it temporarily renders the inmate unconscious so that he/she experiences no pain (the specific drug used for this particular purpose varies from state to state, following production constraints for sodium thiopental)

2) Pancuronium bromide - a neuromuscular blocking agent - paralyzes all voluntary muscles, including the diaphragm, thereby preventing breathing. However, it neither helps in rendering the victim unconscious nor in his/her ability to feel pain; it only restricts the expression of pain. According to medical experts it is unnecessary to use this drug.

3) Potassium chloride - causes a cardiac arrest leading to death - injecting heavy doses can lead to excruciating pain if inmate is not already unconscious.

(According to information from a research paper from Berkeley Law, University of California)

The Single Drug Formula:

A heavy dose of a fast-acting barbiturate is injected intravenously. The drug immediately renders the inmate unconscious and brings about cardiac arrest.

Ohio was the first U.S. state to legalize this method of execution, followed by Washington.

It is believed the single drug injection method is a more humane one, as the chances of an inmate suffering is generally minimal; there is always the chance of regained consciousness and excruciating pain before the injection of potassium chloride, in the alternate method, according to experts quoted in The New York Times.

California state authorities have the option of either appealing Judge D'Opal's ruling or revising procedures to meet required legal norms.