It establishes a Sabbath day on Sunday during which no trade or professional or commercial undertakings are to be pursued.
It applies the writ of Habeas Corpus to its people and provides for the basic rights of the accused, such as protection from double jeopardy.
Tonga is a semi-constitutional monarchy in which the King exercises executive power through his Cabinet.
The constitution can be amended by the Legislative Assembly, provided this does not affect the "law of liberty", the monarchical succession, or the titles or estates of the nobles.
Amendments must pass the Legislative Assembly three times, and be unanimously supported by the Privy Council.