Nigeria

…
And to provide for a Constitution for the purpose of promoting the good government and welfare of all persons in our country, on the principles of freedom, equality and justice, and for the purpose of consolidating the unity of our people
… (Preamble)

(1) The motto of the Federal Republic of Nigeria shall be Unity and Faith, Peace and Progress.
(2) Accordingly, national integration shall be actively encouraged, whilst discrimination on the grounds of place of origin, sex, religion, status, ethnic or linguistic association or ties shall be prohibited.
… (Sec. 15)

(1) The State social order is founded on ideals of Freedom, Equality and Justice.
(2) In furtherance of the social order –
(a) every citizen shall have equality of rights, obligations and opportunities before the law;
… (Sec. 17)

(1) A citizen of Nigeria of a particular community, ethnic group, place of origin, sex, religion or political opinion shall not, by reason only that he is such a person: –
(a) be subjected either expressly by, or in the practical application of, any law in force in Nigeria or any executive or administrative action of the government, to disabilities or restrictions to which citizens of Nigeria of other communities, ethnic groups, places of origin, sex, religions or political opinions are not made subject; or
(b) be accorded either expressly by, or in the practical application of, any law in force in Nigeria or any such executive or administrative action, any privilege or advantage that is not accorded to citizens of Nigeria of other communities, ethnic groups, places of origin, sex, religions or political opinions.
(2) No citizen of Nigeria shall be subjected to any disability or deprivation merely by reason of the circumstances of his birth.
(3) Nothing in subsection (1) of this section shall invalidate any law by reason only that the law imposes restrictions with respect to the appointment of any person to any office under the State or as a member of the armed forces of the Federation or member of the Nigeria Police Forces or to an office in the service of a body, corporate established directly by any law in force in Nigeria. (Sec. 42)