 S/he must have been a lawyer for at least fifteen years to have been eligible for appointment to the Supreme Court in the first place.Where the office of the chief justice is vacant or the chief justice is incapacitated and unable to carry out his duties, the most senior of the justices of the Supreme Court is expected to act in his place until he is able to resume or a new substantive chief justice is appointed by the president.The chief justice and any other justice of the superior courts may voluntarily retire on reaching the age of 60 years or stay on till the compulsory retiring age of 70 years.