Voir Dire is the procedure by which both sides in a trial try to select a jury that will be fair and impartial to the State and to the Defendant. The judge and, at least in state courts, both the prosecutor and the defense attorney ask the potential jurors about their views and whether they can decide fairly.
Each side gets to strike a certain number of potential jurors – in North Carolina, each side gets six peremptory challenges – and excuse those jurors from service without giving a reason at all (although pursuant to Kentucky v. Batson a prosecutor may not exclude jurors solely on the basis of race).
But what happens when potential jurors say they will refuse to follow the law and convict the Defendant for marijuana possession? Here’s a story from Montana, normally considered a conservative state, where potential juror after potential juror expressed the position to the judge that he or she would not convicted the defendant for pot possession.