As California's new lethal injection protocol moves the state towards resuming executions, Kevin Cooper (pictured, left) is seeking clemency from Gov. Jerry Brown on the grounds that he is innocent. Cooper - one of 18 death-row prisoners who have exhausted their court appeals and face execution - was sentenced to death for the 1983 murders of a married couple, their 10-year-old daughter, and the daughter's 11-year-old friend. However, evidence that was suppressed as a result of police and prosecutorial misconduct raises serious questions as to his guilt. The key witness against Cooper was the 8-year-old son of the murdered couple, who was gravely injured, but survived the attack. On the day of the murders, the boy said that three white or Hispanic men had committed the killings, and after seeing photos of Cooper on television, he told his grandmother and a sheriff's deputy that Cooper - who is black - was not the killer. After subsequent interrogations by deputies, in which they misrepresented his recollections, he later identified Cooper as the sole killer and testified to that effect at Cooper's trial. Cooper's lawyers were denied an opportunity to cross-examine him. Prosecutors also presented evidence at trial that shoeprints from the crime scene had to belong to Cooper, because he had recently escaped from prison and the prints matched prison-issued shoes that weren't available to the public. A warden from the prison, however, had provided investigators with information rebutting that assertion, but prosecutors hid the warden's statements from the jury. Police also illegally destroyed blood-splattered pants given to them by a woman who believed her husband had been involved in the murders, eliminating an essential piece of evidence that could have helped Cooper prove his innocence. Finally, independent testing of a blood sample that the state claimed had been drawn from Cooper found two different sets of DNA, meaning that the sample had either been contaminated or deliberately altered. In 2009, the U.S. Court of Appeals for the Ninth Circuit upheld Cooper's conviction, but five judges wrote a strong dissent detailing the misconduct and concluding that it was, "highly unlikely that Cooper would have been convicted," without it.