W. Va. Code § 56-6-12
Either party in any action or suit may, and the court shall on motion of such party, examine on oath any person who is called as a juror therein, to know whether he is a qualified juror, or is related to either party, or has any interest in the cause, or is sensible of any bias or prejudice therein; and the party objecting to the juror may introduce any other competent evidence in support of the objection; and if it shall appear to the court that such person is not a qualified juror or does not stand indifferent in the cause, another shall be called and placed in his stead for the trial of that cause. And in every case, unless it be otherwise specially provided by law, the plaintiff and defendant may each challenge four jurors peremptorily.
W. Va. Code § 56-6-12