As a result, the current monarch is officially titled King of Tuvalu and, in this capacity, he and other members of the royal family undertake public and private functions domestically and abroad as representatives of the Tuvaluan state.

All executive authority is vested in the monarch, and royal assent is required for the Tuvaluan Parliament to enact laws and for letters patent and Orders in Council to have legal effect.

Most of the powers are exercised by the elected members of parliament, the ministers of the Crown generally drawn from amongst them, and the judges and justices of the peace.

The Crown primarily functions as a guarantor of continuous and stable governance and a nonpartisan safeguard against the abuse of power.

The independence constitution provided that Queen Elizabeth II was, at the "request of the people of Tuvalu", the sovereign and head of state of the country.

Her visit was cut short, however, as she was suffering from viral pneumonia; her Private Secretary, Lord Napier, had to take her place at the ceremony.

Her Majesty well remembers the warmth of the traditional Tuvaluan welcome she and the Duke of Edinburgh received on the occasion of her last visit to her people in 1982.

This legislation limits the succession to the natural (i.e. non-adopted), legitimate descendants of Sophia, Electress of Hanover, and stipulates that the monarch cannot be a Roman Catholic and must be in communion with the Church of England upon ascending the throne.

Though these constitutional laws, as they apply to Tuvalu, still lie within the control of the British Parliament, both the United Kingdom and Tuvalu cannot change the rules of succession without the unanimous consent of the other realms, unless explicitly leaving the shared monarchy relationship; a situation that applies identically in all the other realms and which has been likened to a treaty amongst these countries.

[21] This is done in reciprocation to the sovereign's Coronation Oath, wherein they promise to govern the peoples of their realms, "according to their respective laws and customs".

The monarch's, and thereby the viceroy's, role is almost entirely symbolic and cultural, acting as a symbol of the legal authority under which all governments and agencies operate, while the Cabinet directs the use of the royal prerogative, which includes the privilege to declare war and maintain the King's peace, as well as to summon and prorogue parliament and call elections.

[36] The royal prerogative further extends to foreign affairs: the governor-general ratifies treaties, alliances, and international agreements.

The governor-general, on behalf of the monarch, also accredits Tuvaluan high commissioners and ambassadors and receives diplomats from foreign states.

The first page of a Tuvaluan passport reads:[37] "The Governor-General of Tuvalu hereby requests and requires in the name of His Majesty King Charles the Third all those whom it may concern to allow the holder of this passport to pass freely, without hindrance or delay, and in case of need to give the holder all lawful aid and protection.

[citation needed] As all executive authority is vested in the sovereign, royal assent is required to allow for bills to become acts of parliament.

[46] The sovereign, and by extension the governor-general, can also grant immunity from prosecution, exercise the royal prerogative of mercy, and pardon offences against the Crown, either before, during, or after a trial.

The exercise of the power of mercy to grant a pardon and the commutation of prison sentences is described in section 82 of the constitution.

[48][49] Tuvaluans celebrate it with church services and prayers, singing God Save The King and Tuvalu mo te Atua, flag hoisting, public speeches, a royal salute, and a parade.

As the King's Birthday is a public holiday, all government offices, educational institutions, and most businesses are closed for the day.

[57][58] A St. Edward's Crown appears on the police force's badges and rank insignia, which illustrates the monarchy as the locus of authority.

Under Section 163(5) of the Constitution, the Commissioner of Police is appointed by the Head of State, acting in accordance with the advice of the Cabinet given after consultation with the Public Service Commission.

The current oath is:[60] "I, [name], do swear by Almighty God (or solemnly and sincerely affirm) that I will well and truly that I will be faithful and bear true allegiance to His Majesty King Charles the Third, His Heirs and Successors, and that I will faithfully serve His Majesty the King, His Heirs and Successors, during my service in the Tuvalu Police Force: that I will subject myself to all Acts, orders and regulations relating to the said Police now in force or which may from time to time be in force and will discharge all the duties of a police officer according to law, without fear or favour, affection or ill-will.

[61] Princess Margaret arrived in September 1978 to represent the Queen at the independence celebrations, but her visit was cut short by illness.

[62] In February 1986, a nation-wide referendum was held to ask Tuvaluans whether Tuvalu should remain a constitutional monarchy, with the Queen as its head of state, or become a republic.