Namibia

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(3) The following persons shall be citizens of Namibia by marriage:
(a) those who are not Namibian citizens under Sub-Article (1) or (2) hereof and who:
(aa) in good faith marry a Namibian citizen or, prior to the coming into force of this Constitution, in good faith married a person who would have qualified for Namibian citizenship if this Constitution had been in force; and
(bb) subsequent to such marriage have ordinarily resided in Namibia as the spouse of such person for a period of not less than ten (10) years; and
(cc) apply to become citizens of Namibia;
(b) for the purposes of this Sub-Article (and without derogating from any effect that it may have for any other purposes) a marriage by customary law shall be deemed to be a marriage: provided that nothing in this Constitution shall preclude Parliament from enacting legislation which defines the requirements which need to be satisfied for a marriage by customary law to be recognised as such for the purposes of this Sub-Article.
… (Art. 4)

(1) ...
(f) No persons shall be compelled to give testimony against themselves or their spouses, who shall include partners in a marriage by customary law, and no Court shall admit in evidence against such persons testimony which has been obtained from such persons in violation of Article 8(2)(b) hereof.
... (Art. 12)

(1) Both the customary law and the common law of Namibia in force on the date of Independence shall remain valid to the extent to which such customary or common law does not conflict with this Constitution or any other statutory law.
(2) Subject to the terms of this Constitution, any part of such common law or customary law may be repealed or modified by Act of Parliament, and the application thereof may be confined to particular parts of Namibia or to particular periods. (Art. 66)

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(5) There shall be a Council of Traditional Leaders to be established in terms of an Act of Parliament in order to advise the President on the control and utilization of communal land and on all such other matters as may be referred to it by the President for advice. (Art. 102)