Attitudes toward the death penalty are multifaceted and strongly held, but little research outside of the death-qualification literature has focused on the role that such attitudes and beliefs play in jurors’ capital sentencing verdicts. A single item is insufficient to properly measure attitudes toward the death penalty; therefore, a new 15-item, 5-factor scale was constructed and validated. Use of this scale in 11 studies of capital jury decision making found a large effect of general support of the death penalty on sentencing verdicts as well as independent aggravating effects for the belief that the death penalty is a deterrent and the belief that a sentence of life without parole nonetheless allows parole. These effects generally were not completely mediated by, nor did attitudes moderate the effects of, aggravating and mitigating factors. Through death qualification and voir dire, the legal system attempts to strike a balance between jurors’ attitudes toward the death penalty and a defendant’s right to an impartial jury. Courts embrace the fact that capital jurors’ attitudes toward the death penalty influence their decisions whether to sentence a defendant to death: “A jury that must choose between life imprisonment and capital punishment can do little more—and must do nothing less—than express the conscience of the community on the ultimate question of life or death” (Witherspoon v. Illinois, 1968, p. 519). However, the defendant’s right to an impartial jury requires that jurors also be able to follow the law and not reach a verdict based solely on their attitudes. Courts currently balance these interests by allowing parties to exclude for cause only those jurors whose attitude toward the death penalty is so strong, either for or against, that it would “prevent or substantially impair the performance of [their] duties as a juror” (Wainwright v. Witt, 1985, p. 424). To ascertain whether jurors fail this test, defendants are entitled to an adequate voir dire that consists of more than general questions and that is sufficient to allow the defendant to uncover biases to which jurors do not readily admit (Morgan v. Illinois, 1992). Afterward, death-qualified capital jurors must (though the specifics vary by