To prevent the appearance of any bias in the court's makeup, if there was a judge belonging to one member state on the panel and the other member state was not "represented", they had the ability to select an "ad hoc" judge of their own nationality to hear the case. In a full court hearing, that increased the number to 12; in one of the 5-man chambers, the new judge took the place of one of the original 5. That did not apply to summary procedure cases. The "ad hoc" judge, selected by the member state, was expected to fulfil all the requirements of a normal judge; the President of the Court had ultimate discretion over whether to authorise him to sit. The Court was mandated to open on 15 June each year and continue until all cases were finished, with extraordinary sessions if required; by 1927, there were more extraordinary sessions than ordinary ones. The Court's business being conducted in English and French as official languages, and hearings were public unless it was otherwise specified.