Jamaica is a parliamentary democracy and constitutional monarchy. The head of state is the Queen of Jamaica (currently Queen Elizabeth II), represented locally by the Governor-General of Jamaica. The governor-general is nominated by the Prime Minister of Jamaica and the entire Cabinet and then formally appointed by the monarch. All the members of the Cabinet are appointed by the governor-general on the advice of the prime minister. The monarch and the governor-general serve largely ceremonial roles, apart from their reserve powers for use in certain constitutional crisis situations. The position of the monarch has been a matter of continuing debate in Jamaica for many years; currently both major political parties are committed to transitioning to a republic with a president.

Jamaica’s current constitution was drafted in 1962 by a bipartisan joint committee of the Jamaican legislature. It came into force with the Jamaica Independence Act, 1962, which was passed by the Parliament of the United Kingdom, which gave Jamaica independence.
https://en.wikipedia.org/wiki/Jamaica