Since your a former prosecutor, by excusing all jurors who had such reservations about the death penalty, didn’t they also create a jury that might have been slanted for the underlying decision, not just the penalty phase?
No question, a juror that expresses reservation could also have reservations about conviction...but not as a rule, most people have reservations about the death penalty before they hear the evidence. It’s hard to say you would definitely kill someone before you know all the facts. With that said, whenever a juror says...under oath that they will follow the judges instructions and the law...they cannot be excluded “for cause” for expressing a reservation. That is settled law in every jurisdiction.