The Constitution stipulates that the king is "enthroned in a position of revered worship" and is not to be exposed "to any sort of accusation or action." As ceremonial head of state, the monarch is endowed with a formal power of assent and appointment, is above partisan affairs, and does not involve himself in the decision-making process of the government. In the 1980s, King Bhumibol Adulyadej remained the nation’s most respected figure because he was popularly perceived to be the embodiment of religion, culture, and history. He ensured political stability and unity by lending legitimacy to important government actions and, in potentially destabilizing situations, as during the abortive coups in 1981 and 1985, by discreetly signaling his support of the incumbent government.
In discharging his formal duties, the king was assisted by the Privy Council, whose president and not more than fourteen members were royal appointees. These members could not hold other public offices, belong to political parties, or show loyalty to any partisan organization. Also assisting the king were the Office of His Majesty’s Principal Private Secretary and the Bureau of the Royal Household, agencies responsible for organizing ceremonial functions and administering the finances and logistics of the royal palace.
The mode of succession was set forth in the Palace Law on Succession. In the absence of a crown prince, or if the crown prince declined succession, a princess could succeed, subject to parliamentary approval. When the throne became vacant, an heir was to be appointed by the Privy Council. Until the heir formally ascended the throne, the president of the Privy Council would act as regent. Prince Vajiralongkorn, the only son of King Bhumibol and Queen Sirikit, was designated as heir on December 28, 1972, at the age of twenty.