It's called a "peremptory challenge". In TN, the prosecution gets some and so does the defense.

http://www.answers.com/topic/peremptory-challenge


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>How is this different from a civilian trial where both sides routinely reject jurors who may hold views that they feel won't benefit their client? Each side gets a certain number of rejections for every trial. So in essence, both sides get to "stack the deck" in a sense - or at least until their juror refusals run out.... this looks to me like a media attempt to make a story where one does not exist - or at least is no different than any other jury trial.