This paper presents the first quantitative study of Witherspoon strikes in real capital cases, measuring the strike rate in eleven Louisiana trials resulting in death verdicts from 2009 to 2013. Of the 1,445 potential jurors questioned, 325 individuals (22.5%) were excluded from service on the basis of their opposition to the death penalty. These exclusions had a considerable impact on the racial composition of the jury pool: In the trials for which individualized data on race was available, one-third of black venire members were struck under Witherspoon, and nearly 60% of those struck on this basis were black. These findings underscore the profound impact of death qualification upon the composition of capital juries and the outcomes of capital trials. Particularly in the wake of Justice Breyer’s recent call for reconsideration of the death penalty’s constitutionality, there is an urgent need for (a) systematized, ongoing data collection on Witherspoon strikes, and (b) formal consideration of the effect of death qualification in future Eighth Amendment analysis.