The Senator behind this is Ahmed Yerima, who married a 13y/o Egyptian child. He's obviously trying to justify that. The truth however is that Yerima, the other Senators who supported him and a majority of Nigerians do not know the law.
Section 29 of the Nigerian Constitution provides:
(1) Any citizen of Nigeria of full age who wishes to renounce his Nigerian citizenship shall make a declaration in the prescribed
manner for the renunciation.
(2) The President shall cause the declaration made under subsection (1) of this section to be registered and upon such
registration, the person who made the declaration shall cease to be a citizen of Nigeria.
(3) The President may withhold the registration of any declaration made under subsection (1) of this section if-
(a) the declaration is made during any war in which Nigeria is physically involved; or
(b) in his opinion, it is otherwise contrary to public policy.
(4) For the purposes of subsection (1) of this section,
(a) "full age" means the age of eighteen years and above;
(b) any woman who is married shall be deemed to be of full age.
Section 29 deals with renunciation of citizenship alone.
The senators wanted to remove Section 29(4)(b) because it seemed to echo 29(4 (a). Please note that Section 21 of the Child's Rights Act stipulates 18 years as the age of marriage and nullifies any marriage that falls below this with a punishment of N500,000 or a 5 year jail term, or both for offenders.
The now famous Section 29 clearly has nothing to do with the age at which a woman can get married but at what age and status Nigerian woman can renounce her citizenship. In fact, I think Senator Yerima has done more harm to himself because this means that his Egyptian wife can renounce her Nigerian citizenship and leave him and the country.
IMO, Nigerians should rather focus on kicking against the culture that promotes under age marriage by coming under the Child Rights Act.