Ernest "Ernie" Walker was a small time thief falsely convicted for murder.
Walker was a small-time thief. He wasn't exactly the nicest guy around, but he abhorred violence. It came to a complete shock to him when he was accused of murdering a woman.
Police suspected Walker because he tried to sell the victim's necklace to a fence. His alibi, that he had been at home eating pizza and found the necklace on his doorstep, was dismissed by Detective Bowman. Unable to afford a good defense, he was assigned a public defender, who did not check up on his alibi. Walker was found guilty, and sentenced to death.
He wasted away five years on death row at Stryker's Island. Less than a week before his scheduled execution, Walker still claimed he was innocent. Clark Kent heard his case and investigated it. Though he found exculpatory evidence, the actual killer—Detective Bowman—managed to "kill" Clark and destroy the evidence.
Walker was led to the gas chamber, strapped in, and the executioner released the gas. He cowered as the gas inched closer. At that moment, Superman burst into the room. He broke into the chamber, and sucked the gas out. With the real killer in custody, Walker was cleared of all charges.