(a) In civil cases each party shall be entitled to three peremptory challenges. Several defendants or several plaintiffs shall be considered as a single party for the purpose of making challenges. If there is more than one defendant the court may allow the defendants additional peremptory challenges and permit them to be exercised separately or jointly.
(b) All challenges for cause or favor, whether to the array or panel or to individual jurors, shall be determined by the court.