For a case to be concluded in a Court to the point of delivery of judgement, the parties to the case must prove their case. One way of proving their case is by calling Witnesses whose testimonies will be admitted into evidence and form the basis of the judgement of the Court. According to the Longman Dictionary of Contemporary English, “a Witness is someone who sees a crime or an accident or can describe what happened”. The Black Law Dictionary gives two definitions of a Witness “a person who signs a document or a person called to Court to testify or give Witness”.
The general rule as stated in Section 175 (1) of the Evidence Act (EA) is that all persons are competent Witnesses. However, this rule is not without exceptions. Therefore, there are circumstances where a person is deemed not to be a competent witness and other circumstances where a competent witness cannot be compelled to give evidence in Court. It should be noted that all compellable witnesses are competent Witnesses. Section 175 (1) has listed the non-competent Witness to include: Children, extremely old age persons, persons with a disease of the body or mind, and any other cause similar to the above. These exceptions will be discussed below and likewise the non-compellable Witnesses.
Exceptions to the General Rule
A child has been defined by Section 209 of the (EA) to mean, a person below the age of 14 years. It further stated that when a child below the age of 14 years is tendered as a Witness, such child will not be sworn and will give evidence otherwise than on oath affirmation, if it is in the opinion of the court that the child possessed sufficient intelligence to justify his evidence and understands the duty of speaking the truth. Therefore, the Court in determining the level of understanding of the obligation to say the truth by the child, will ask preliminary questions to the child based on the ability to perceive and remember the facts of the case. If the Court can determine the level of understanding of the child, such a child will be deemed to be a competent Witness and the child’s testimony will be unsworn. However, a conviction cannot be based solely on unsworn evidence of a child, such evidence must be corroborated.
- Persons of Weak Intellect
Section 175 (2) EA clearly states that a person of unsound mind is not an incompetent witness except if he is prevented by the infirmity from understanding the questions put to him and giving rational answers to them. Therefore, to determine if such a person has sufficient understanding to give rational evidence and understands the obligation to say the truth, the Court will ask preliminary questions just as in the case of a child. If the Court is satisfied with the response, then he will be deemed to be a competent witness. This practice also applies to persons of extreme old age, and persons with a disease of the body or mind.
- Dumb Persons
According to Section 176 of the (EA), a dumb person is both a competent and compellable witness. The evidence of a dumb person is taken either by sign language or a written statement. Such evidence is treated as oral evidence.
- Parties in Civil and Criminal Proceeding and their Spouses
According to Section 178 of the (EA), in all civil proceedings, the parties to the Suit and the husband or wife of any party to the Suit shall be competent witnesses. Also in criminal proceedings, the Defendant’s his wife or her husband as the case may be, or any person jointly charged with such defendant and tried at the same time, and the wife or husband of the person so jointly charged, is competent to testify.
In a criminal case, the spouse of an accused is a competent witness for the defendant and can be a competent and compellable witness to the prosecution in the following instances below:
- Where the consent of the accused is not required: according to Section 182 (1), where the defendant is charged with an offence listed in this section (offences against the husband or wife and sex-related offence), the spouse of the Defendant is a competent and compellable witness for the prosecution, the consent of the accused is not required.
- Where the consent of the accused is required: according to Section 182 (2), where the spouse is charged with an offence not listed in Section 182 (1), the husband or wife is a competent and compellable witness only with the consent of the spouse charged.
Privilege Communication: Section 182 (3&4) provides for communication between husband and wife. Therefore, communication made by a man to his wife or a woman to her husband during their marriage is deemed privileged communication. They are competent witnesses but not compellable witnesses.
- The Defendant
Section 36 (11) of the 1999 Constitution (as amended) provides for the Defendant’s right to silence. No person who is tried for a criminal offence shall be compelled to give evidence. But under Section 180 (a) of the EA, the Defendant on his or her own application is a competent witness in his or her defence or in the defence of a co-accused. In this circumstance, the Defendant will give evidence from the witness box, not the dock.
Subsection 180 (b) of the Act provides that if the Defendant testifies on his or her own application, he or she may be asked any question in cross-examination even if the answer would tend to incriminate him or her as to the offence charged. Hence, the effect of the defendant testifying abrogates the right against self-incrimination which the Defendant would otherwise enjoy under Section 36 (11) of the 1999 Constitution (as amended).
A Co-defendant is competent and compellable in the following instances;
- If the co-defendants are charged separately, the defendant is a competent and compellable witness for the prosecution and the defence.
- But if the accused persons are charged jointly, the co-defendant is neither a competent nor compellable witness for the prosecution or the defence unless:
- The co-defendant is tried separately;
- The co-defendant has been acquitted of the offence;
- The charge against the co-defendant has been withdrawn; a nolle prosequi is entered for the co-defendant;
- The co-defendant pleads guilty to the offence and is convicted.
Nevertheless, if the Defendants are tried jointly, evidence given by one of them is admissible against the Co-defendant notwithstanding that the evidence is incriminating.
According to Section 198 (1) of the (EA), an accomplice is a competent witness for the prosecution against the Defendant. The evidence of an accomplice, on the other hand, should be corroborated.
A conviction based solely on the uncorroborated evidence of an accomplice is not illegal. Provided, that if the only evidence against a defendant charged with a criminal offence is the evidence of an accomplice, which is uncorroborated in any material particular implicating the defendant, the court shall direct itself that it is unsafe to convict anyone on such evidence.
- Legal Practitioners
Section 192 of the EA provides:
- No legal practitioner shall at any time be permitted unless with his client’s express consent, to disclose any communication made to him in the course and for the purpose of his employment as such legal practitioner by or on behalf of his client, or to state the contents or condition of any document with which he has become acquainted in the course and for the purpose of his professional employment or to disclose any advice given by him to his client in the course and for the purpose of such employment:
Provided that nothing in this section shall protect from disclosure:
- any such communication made in furtherance of any illegal purpose; or
- any fact observed by any legal practitioner in the course of his employment as such, showing that any crime or fraud has been committed since the commencement of his employment.
- It is immaterial whether the attention of such legal practitioner was or was not directed to such fact by or on behalf of his client.
- The obligation stated in this section continues after the employment has ceased.
Though a Counsel is a competent witness, it is not proper for them to give evidence in a Matter in which he or she appears as Counsel, according to the Rules of Professional Conduct for Legal Practitioners. Subject to the exception in Subsection 192 (1) (a) (b) of the Act, no Counsel shall at any time be permitted to disclose any communication made to him in the course of his employment as Counsel, unless with his client’s express consent.
- Non-compellability by virtue of office
Under Section 308 of the 1999 Constitution (as amended),
- The President, Governors and their Deputies have immunity against prosecution while in office. Therefore, they are competent but not compellable witnesses.
- Section 1 (1) of the Diplomatic Immunities and Privileges Act confers on Diplomats, Members of their families and Staff immunity against prosecution. Therefore, they are competent but not compellable witnesses.
- Based on policy, a Judge or Magistrate is neither a competent nor compellable witness in respect of a case pending before him or her as a Judge or Magistrate.
For the testimony of a Witness to be admitted into evidence, such witness must be a competent witness. However, not all competent witnesses can be compelled to give evidence.
 Section 209(3) of the (EA)
 Rule 20 Rules of Professional Conduct