Answer: He called him a self-appointed public avenger and a sadist.
Juror #3 was upset that some of the other jurors seemed to be listening to Juror #8. "What's the matter with you guys?" he cried, "You all know he's guilty. He's got to burn. You're letting him slip through our fingers." This made him sound more like an executioner than a juror, so Juror #8 asked him if he would like to "pull the switch", to which Juror #3 replied affirmatively. "I feel sorry for you," said Juror #8. "What it must feel like to want to pull the switch. Ever since you walked into this room, you've been acting like a self-appointed public avenger. You want to see this boy die because you personally want it - not because of the facts. You're a sadist!" This proved to be too much for Juror #3, who lunged at Juror #8 while yelling, "I'll kill him!" Unfortunately for Juror #3, this only undermined a point that he had previously made. Earlier, Juror #8 had argued that the phrase "I'm gonna kill you" was used by people thousands of times every day, so even if the defendant had said it to his father, it didn't necessarily mean that he killed him. Juror #3 disagreed. "The kid yelled it at the top of his lungs. Don't tell me he didn't mean it. Anybody says a thing like that the way he said it, they mean it," he said. With his outburst, Juror #3 had just contradicted himself. "You don't really mean you'll kill me, do you?" said Juror #8, driving home the point. The next vote resulted in the twelve jurors being split down the middle, after Jurors #2 and 6 changed their votes to "not guilty".