In any criminal action tried before a jury, either party shall have the right to examine, personally or by his counsel, each juror outside the presence of other prospective jurors as to his qualifications to sit as a juror in the action, or as to his interest, if any, in the subject matter of the action, or as to his relations with the parties thereto. If the judge before whom the examination is held is of the opinion from the examination that any juror would be unable to render a fair and impartial verdict, the juror shall be excused by the judge from any further service upon the panel, or in the action, as the judge determines. The right of such examination shall not be abridged by requiring questions to be put to any juror in writing and submitted in advance of the commencement of said action.