The Constitution (adopted in 1991, last amendment in 2016) defines Zambia as a unitary, indivisible, multi-ethnic, multi-racial, multi-religious, multi-cultural and multi-party democratic state. The electoral system is based on universal adult suffrage and equality of votes. The executive authority of Zambia vests in the President who exercises it, subject to the Constitution, through the Cabinet. The President is the Head of State and Government, and the Commander-in-Chief of the Defence Forces. The Constitution vests legislative authority in the legislature, which consists of the National Assembly. Judicial authority is vested in the Judiciary, with the Supreme Court and the Constitutional Court being the superior courts of record.

Zambia’s legal system consists of: laws enacted by Parliament; statutory instruments; Zambian customary law consistent with the Constitution; and the laws and statutes that apply or extend to Zambia, as prescribed. The Constitution is the supreme law of the Republic of Zambia and any other written law, customary law or customary practice that is inconsistent with its provisions is void to the extent of the inconsistency. A matter relating to the Constitution shall be heard only by the Constitutional Court.

The laws that may apply or extend to Zambia are provided for in the  English Law (Extent of Application) Act : these are (a) the common law; (b) the doctrines of equity; (c) the statutes which were in force in England on the 17 August 1911 (i.e. the commencement of the Northern Rhodesia Order in Council, 1911); and (d) any statutes of later date than that mentioned in paragraph (c) in force in England, now applied to the Republic, or which hereafter shall be applied thereto by any Act or otherwise.

With regard to international conventions, Zambia follows the dualist system (international or regional instruments must be incorporated into internal law by a special enabling statute to become binding) even if the Constitution does not explicitly provide for the status of international law in the Zambian legal system. Article 92 states that ‘the President shall negotiate and sign international agreements and treaties and, subject to the approval of the National Assembly, ratify or accede to international agreements and treaties.’ and Article 63 states that : ‘the National Assembly shall oversee the performance of executive functions (…) by approving international agreements and treaties ‘before these are acceded to or ratified’.