Witherspoon v. Illinois

The precise effect of the Witherspoon decision has been difficult to quantify. On one level, the decision continues to serve as precedent for the proposition that the federal Constitution protects criminal defendants from being sentenced by biased juries. However, the contours of Witherspoon's meaning were reshaped by the Court in Wainwright v. Witt. In Witherspoon, the Court had stated that a person may be excluded from a jury only if that person makes it "unmistakably clear" that he or she cannot be impartial or will cast an automatic vote against the death penalty. In Witt, the Court held that a juror may be excluded if it appears that her views on the death penalty will "prevent or substantially impair" the performance of her duties.

On another level, the Witherspoon decision continues to serve as precedent for the proposition that the federal Constitution protects criminal defendants from being sentenced by biased juries. While the Witherspoon Court upheld the right to challenge a juror because of biase against the death penalty, it paved the way for a later ruling in Morgan v. Illinois giving criminal defendants the right to challenge jurors for cause based on a bias in favor of the death penalty.