Introduction
Nigeria’s civil (and many criminal) trials lean heavily on witness statements on oath (WSO). Section 13 of the Oaths Act 2004 and the First Schedulesit at the centre of their validity, while recent appellate decisions show when defects are fatal and when the courts will treat them as mere irregularities. This post distills the statute and the cases counsel most often cite in the courtroom skirmishes over WSOs.
What Section 13 actually does
Section 13, Oaths Act 2004: it is lawful for a Commissioner for Oaths, Notary Public, or other authorised person to administer an oath and take the declaration of a person making it before him, in the form set out in the First Schedule.
Practical takeaways
The deponent must appear before an authorised person. The declaration should track the First Schedule form (e.g., “I do solemnly and sincerely declare…”). The authorised person signs/stamps and identifies their office.
Saving provisions you shouldn’t forget
Section 4(2)–(3) of the Oaths Act softens the edges: irregularity in the form of an oath does not (a) invalidate proceedings or (b) render evidence inadmissible;and failure/irregularity in form does not affect a witness’s duty to tell the truth. These provisions power a long line of “substantial compliance” decisions and frequently decide objections that are purely about format rather than authority/presence.
The presumption of regularity—and how to rebut it
Courts presume that an affidavit/WSO purporting to have been sworn was properly sworn before a person authorised to administer oaths (see Evidence Act ss. 111–112, applied in cases like Umar v. Katagun (2022) LPELR-58147 (CA).
But it’s a rebuttable presumption: if cross-examination or other evidence shows the deponent actually signed in counsel’s office and not before an authorised person, the WSO’s competency can collapse.
The strict line: defects that can be fatal
Some decisions take a hard view where the defect goes to substance (no oath before an authorised person; unsigned deposition; depositions never filed where mandatory):
Abubakar v. INEC (2022) 8 NWLR (Pt. 1833) 463: where a witness’s testimony rests on a fundamentally defective WSO, it is as if no evidence was given at all.
Aliyu v. Bulaki (2019) LPELR-46513 (CA): evidence on a fundamentally defective deposition is inadmissible; you cannot place something on nothing.
SEDC West Multipurpose Co-op Soc. Ltd v. SEC (2019) LPELR-48164 (CA): an unsigned WSO is worthless.
Yabo v. Habib (2022) LPELR-58350 (CA):absence/incompetence of required WSOs is a fundamental defect, not a curable irregularity.
Maikudi v. Wada (2018) LPELR-46004 (CA); Ebundon v. IT of RCCG (2020) LPELR-50756 (CA): no WSO for a defence to counterclaim = defence abandoned, judgment can follow on minimal proof.
This means that If the WSO is not sworn before an authorised person, not signed, or not filed at all where rules mandate, courts treat it as substantive, not cosmetic.
The cure-by-adoption and substantial-compliance line
A parallel line says many defects tied to form can be cured when the witness appears and adopts the statement on oath in open court, and/or are neutralised by Section 4(2)–(3) Oaths Act:
Akeredolu v. Registered Trustees of GOFAMINT (2022) LPELR-57840 (CA) (relying on Udeagha v. Omegara): adoption can cure defects.
NWOGU v. SCOA (Nig.) Ltd (2018) LPELR-49785 (CA):distinguishes affidavits from WSOs; adoption in court “cures” earlier oath-form defects.
Access Bank v. Modakol (Nig.) Ltd (2022) LPELR-57562 (CA):non-replication of First Schedule wording is a form issue; Section 4(2)–(3) shields admissibility.
Sangorayi v. Omoloso (2024) LPELR-62514 (CA): substantial compliance with the Oaths Act suffices; minor deviations in wording don’t invalidate.
Adedibu v. Lawal (2022) LPELR-57360 (CA): adoption in court distinguishes WSOs from affidavits and can rescue earlier irregularities.
MBANEFO & Brothers (Nig.) Ltd v. Adegbenga-Adelakun (2025) LPELR-81903 (CA): adoption + failure to object in time can foreclose later competency attacks.
This means that if the defect is about the formula/wording (First Schedule phrasing, label used, etc.),courts lean to substantial compliance and the curative effect of adoption—especially where no timely objection was taken.
Timing matters: object early or forever hold your peace
Several cases stress that objections should be raised when the witness seeks to adopt the WSO. If you keep quiet, adopt, and even cross-examine, an objection later on appeal may be too late (MBANEFO & Brothers (Nig.) Ltd v. Adegbenga-Adelakun (supra).
Special notes from decided cases
Ashiru v. INEC (2020) 16 NWLR (Pt. 1751) 416:physical appearance before a Commissioner for Oaths is required; if not, the defect is fundamental and the deposition may be discountenanced.
Umar v. Katagun (2022): you may rebut the presumption of regularity by showing the deposition was sworn in counsel’s office (unless counsel is a Notary Public and the formalities are proper).
Usman v. First Bank (2019) LPELR-47086 (CA): an earlier WSO can be used in cross-examination to impeach credibility where later testimony departs from earlier sworn assertions.
Hamisu v. Abacha (2023) LPELR-60476 (CA): a subpoenaed witness (especially to tender documents) need not have a WSO.
Reconciling the “strict” vs “cure” approaches
1. No oath at all / not before authorised person / unsigned / sworn before conflicted officer (Evidence Act s.112)→ Substantive defect → Fatal; evidence may be expunged (e.g., Aliyu v. Bulaki, SEDC, Ashiru).
2. Oath taken before authorised person but form/wording deviates from First Schedule→ Form defect → Often saved by s.4(2)–(3) Oaths Act and/or adoption (e.g., Access Bank v. Modakol, Sangorayi, NWOGU).
3. Procedural lapses like failing to file WSOs where mandatory (e.g., for a defence to counter-claim)→ Jurisdictional/threshold problem → Claim/defence can be treated as abandoned (e.g., Maikudi, Ebundon).
Courtroom strategy: how to raise (or resist) objections
If you are objecting
1. Pin down the defect as substantive: lack of authorised officer, absence of signature, sworn before a person barred by s.112 Evidence Act, or no WSO where rules mandate one.
2. Elicit admissions on where it was signed and who administered the oath—rebut the presumption of regularity.
3. Object at adoption; don’t wait until address/appeal.
If you are resisting
1. Argue s.4(2)–(3) Oaths Act:defect is about form, not substance.
2. Emphasize adoption in open court cured any earlier irregularity (cite Udeagha v. Omegara, NWOGU, Access Bank v. Modakol).
3. Point to waiver:no timely objection at adoption; cross-examination proceeded (MBANEFO line of cases).
4. Invoke presumption of regularity unless convincingly rebutted (Umar v. Katagun distinguishes when it is).
Drafting checklist for legally compliant WSOs
1. ☐ Appear before: Commissioner for Oaths / Notary Public / other authorised officer.
2. ☐ Identify the officer (name, capacity) and ensure signature/seal/stamp and date are plain on the face.
3. ☐ Use First Schedule language or an obviously equivalent declaration (avoid calling it merely an “affidavit” where you mean WSO).
4. ☐ Deponent signs in the presence of the authorised officer.
5. ☐ Illiterate jurat where required.
6. ☐ Avoid counsel’s office (unless counsel is Notary Public and the formalities are strictly observed).
7. ☐ File all mandatory WSOs (e.g., for defence to counter-claim).
8. ☐ At trial, adopt the WSO cleanly; be ready to tender referenced exhibits.
9. ☐ Object early (if on the other side) or insist on adoption (if defending).
Handy model closing (First Schedule-style) clause
“I, [Full Name], do solemnly and sincerely declare that the facts stated in this witness statement on oath are true and correct to the best of my knowledge, information and belief; and I make this solemn declaration conscientiously believing the same to be true, and by virtue of the provisions of the Oaths Act.”
(Then ensure the Commissioner for Oaths/Notary signs, dates, and seals with his/her designation.)
Conclusion
1. Get the substance right (authorised officer + in-person swearing + signature/seal).
2. Aim for the First Schedule form, but know s.4(2)–(3) often saves minor form glitches—especially after adoption.
3. Object early to knock out truly defective WSOs; adopt promptly to shore up irregular ones.
4. Never skip mandatory WSOs (e.g., for a defence to counter-claim).
Disclaimer
This article is for general information and educational purposes only; it is not legal advice and does not create a lawyer–client relationship. Laws, rules, and judicial attitudes evolve, and outcomes turn on specific facts. For advice on any specific matter, please consult a qualified legal practitioner.
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