The Jordanian constitution
effective from 1965 (when it was amended to allow the king to take a brother as heir) till KHussein's death (and afterwards).
KHussein considered several times after 1965 to amend the constitution again (in favor of - at first - PAli or - later - PHamzah). But at the end of the day he never did.
CHAPTER FOUR
The Executive Power
Part I
The King and His Prerogatives
Article 28 The Throne of the Hashemite Kingdom of Jordan is hereditary to the dynasty of King Abdullah Ibn Al-Hussein in a direct line through his male heirs as provided hereinafter:
(a) * The Royal title shall pass from the holder of the Throne to his eldest son, and to the eldest son of that son and in linear succession by a similar process thereafter. Should the eldest son die before the Throne devolves upon him, his eldest son shall inherit the Throne, despite the existence of brothers to the deceased son. The King may, however, select one of his brothers as heir apparent. In this event, title to the Throne shall pass to him from the holder of the Throne.
* As amended in the Official Gazette No. 1831 of 1/4/1965
(b) Should the person entitled to the Throne die without a male heir, the Throne shall pass to his eldest brother. In the event that the holder of the Throne has no brothers, the Throne shall pass to the eldest son of his eldest brother. Should his eldest brother have no son, the Throne shall pass to the eldest son of his other brothers according to their seniority in age.
(c) In the absence of any brothers or nephews, the Throne shall pass to the uncles and their descendants, according to the order prescribed in paragraph (b) above.
(d) Should the last King die without any heir in the manner prescribed above, the Throne shall devolve upon the person whom the National Assembly shall select from amongst the descendants of the founder of the Arab Revolt, the late King Hussein Ibn Ali.
(e) No person shall ascend the Throne unless he is a Moslem, mentally sound and born by a legitimate wife and of Moslem parents.
(f) No person shall ascend the Throne who has been excluded from succession by a Royal Decree on the ground of unsuitability. Such exclusion shall not of itself include the descendants of such person. The Royal Decree of exclusion shall be countersigned by the Prime Minister and by four Ministers, at least two of whom shall be the Minister of Interior and the Minister of Justice.
(g) The King attains his majority upon the completion of his eighteenth year according to the lunar calendar. If the Throne devolves upon a person who is below this age, the powers of the King shall be exercised by a Regent or Council of Regency, who shall have been appointed by a Royal Decree by the reigning King. If the King dies without making such nomination, the Council of Ministers shall appoint the Regent or Council of Regency.
(h) Should the King become unable to exercise his powers on account of illness, his powers shall be exercised by a Viceregent or Council of Viceregents. The Viceregent or Council of Viceregents shall be appointed by Royal Decree. Should the King be unable to make such appointment, such shall be made by the Council of Ministers.