The word “crime” is derived from the Latin word “Crimen” meaning an accusation. The Constitution and both the Penal and the Criminal Codes contain references or definitions of crime which you need to be familiar with.
The Constitution section 36: Right to fair hearing:
(a) Sub-section:No person shall be held to be guilty of a criminal offence on account of any act or omission that did not, at the time it took place, constitute such an offence, and no penalty shall be imposed for any criminal offence heavier than the penalty in force at the time the offence was committed.
(b) “……a person shall not be convicted of a criminal offence unless that offence 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 provision of a law”
Section 13
All authorities and persons exercising judicial powers shall conform to, observe an d apply the provisions of the provisions of the constitution
Section 17
The independence, impartiality and integrity of courts and easy accessibility thereto shall be secured and maintained
The Penal Code
(a) Section 3: Punishment of offences
(i) Every person shall be liable to punishment under the Penal code for every act or omission contrary to the provisions thereof of which he shall be guilty within the Northern States.
(ii) After the commencement of this law, no person shall be liable to punishment under any native law or custom.
(b) Section 4. Offences against laws of a state:
(i) Whereby the provision of any law of state in the North, the doing of any act or the making of any omission is made a offence, those provisions shall apply to every person who is in Northern Nigeria at the time of his doing the act or making the omission.