The powers of the President of Singapore are divided into those which the largely ceremonial President may exercise at his own discretion, and those he must exercise in accordance with the advice of the Cabinet of Singapore or of a Minister acting under the general authority of the Cabinet. In addition, the President is required to consult the Council of Presidential Advisers (CPA) when performing some of his functions. In other cases, he may consult the CPA if he wishes to but is not bound to do so.
In 1991 the Constitution of Singapore was amended to transform the office of President, which was previously indirectly elected by Parliament into an office directly elected by the people. The amendment conferred on the President certain executive functions to block attempts by the government of the day to draw down past reserves that it did not accumulate. Thus, a guarantee may only be given or a loan raised by the Government if the President concurs, and his approval is also needed for budgets of specified statutory boards and Government companies that draw on their past reserves. The President also possesses personal discretion to withhold assent to any bill in Parliament providing directly or indirectly for the direct or indirect variation, changing or increase in powers of the Central Provident Fund Board to invest moneys belonging to it; and the borrowing of money, the giving of any guarantee or the raising of any loan by the Government if in the President's opinion the bill is likely to draw on reserves not accumulated by the Government during its current term of office. In addition, the President may withhold assent to any Supply Bill, Supplementary Supply Bill or Final Supply Bill for any financial year if in his opinion the estimates of revenue and expenditure, supplementary estimates or statement of excess are likely to lead to a drawing on past reserves.
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The President is also empowered to approve changes to key civil service positions, such as the Chief Justice, the Attorney-General, the chairman and members of the Public Service Commission, the Chief of Defence Force and the Commissioner of Police. He also appoints as Prime Minister a Member of Parliament (MP) who, in his personal judgment, is likely to command the confidence of a majority of MPs. The President has certain powers of oversight over the Corrupt Practices Investigation Bureau and decisions of the Executive under the Internal Security Act and the Maintenance of Religious Harmony Act.