Is Adultery a Crime in Nigeria?

Adultery is the voluntary sexual intercourse between a married person and a person who is not their spouse. The difference between adultery and  fornication is that while the later is a voluntary sexual intercourse between unmarried couple, the former is a voluntary sexual intercourse between a person who is statutorily married and another person who is not his or her spouse.

The offense of adultery can be a valid ground for separation of marriage or divorce (if the other partner finds the extra marital affairs intolerable). A partner can file for divorce solely on the ground that the other partner is having extra marital affairs and that extra marital affairs have caused the irretrievable breakdown of the marriage.

While adultery can serve as a ground for divorce, it should however be noted that it is not a crime in Southern states of Nigeria, hence a partner cannot be punished for cheating on the other partner especially in the southern region of Nigeria.(Southern region here loosely comprises of the South South, South East and South West). 

This principle was established by the Supreme Court in 1961 in the old case of Aoko v. Fagbeyemi (1961) 1 ALL NLR 400, where the court  held that a woman who has been accused of cheating on her husband could not be convicted for adultery in the southern states of Nigeria because adultery was not prescribed as an offense in any written law in those states. This case also serves as a locus classicus to the constitutional principle that on no account should a person be punished for any offense or whatsoever that is not prescribed as an offense in any written law in Nigeria.

This principle was the highlight of s.36(12) of the 1999 constitution (as amended) which reads thus: “Subject as otherwise provided by this Constitution, a person shall not be convicted of a criminal offense unless that offense is defined and the penalty therefore is prescribed in a written law, and in this subsection, a written law refers to an Act of the National Assembly or a Law of a State, any subsidiary legislation or instrument under the provisions of a law”.

While in the Southern part of Nigeria where the Criminal Code Act applies, adultery is not a criminal offense, the law however considers adultery a criminal offense in Northern Nigeria where the Penal Code and sharia law  applies.

Section 387 and 388 stipulate the punishment of imprisonment for two years, and/or with a fine for the crime of adultery committed in that region. 

So to answer the question; “whether adultery is a crime in Nigeria”? the answer will depend on what region of Nigerian law applies to you. If you are in Northern states, Yes,  adultery is a crime and you can go to jail for the crime of adultery but if you are in Southern region, then No, adultery is not a crime.

In summary, under the Nigerian criminal justice system, the country is polarized into two criminal laws: the Criminal code and the Penal code/Sharia Law. While the Criminal code is applicable to Southern  Nigeria, the Penal code and Sharia law is applicable to the Northern states. Under the criminal code, adultery is not a crime, hence,  a person cannot be punished for adultery in Southern Nigeria but a person can be punished with 2 years imprisonment term and or with a fine in Northern Nigeria where the penal code/ Sharia law applies.