Adams v. Texas
In Adams v. Texas, 448 U.S. 38, 50-51, 100 S.Ct. 2521, 65 L.Ed.2d 581 (1980), the Supreme Court reversed the death penalty when Texas courts excluded prospective jurors "who stated that they would be `affected' by the possibility of the death penalty, but who apparently meant only that the potentially lethal consequences of their decision would invest their deliberations with greater seriousness and gravity or would involve them emotionally." Id. at 49, 100 S.Ct. 2521.
"But neither nervousness, emotional involvement, nor inability to deny or confirm any effect whatsoever is equivalent to an unwillingness or an inability on the part of the jurors to follow the court's instructions and obey their oaths, regardless of their feelings about the death penalty." Id. at 50, 100 S.Ct. 2521.