NNH Op-Ed Legal Desk: Judicial Self-Correction in Nigeria – The Power of a Judge to Vacate His Own Judgment, Functus Officio, and the Slip Rule Doctrine

By NNH Legal Desk Analyst

In a significant ruling delivered on Friday at the Federal High Court sitting in Lokoja, Kogi State, Justice Isah Dashen vacated the court’s earlier judgment of December 2025, which had directed the Independent National Electoral Commission (INEC) to register the Nigeria Democratic Congress (NDC) as a political party. The decision followed an application by the Peace Movement Party (PMP), which argued that it was a necessary party whose interests (particularly regarding a disputed party logo) were affected without being heard.

Justice Dashen held that the prior judgment was “constitutionally defective” due to the breach of fair hearing (*audi alteram partem*), ordered the substantive suit to commence afresh with all relevant parties (INEC, PMP, and NDC) joined, and restored the status quo ante pending final determination. This development raises important questions about judicial powers: Does a judge have the authority to overrule or set aside his own decision? How does the doctrine of *functus officio* apply? And what role does the slip rule play in such scenarios?

Contrary to the misconception that only appellate courts or the Supreme Court can interfere with judgments, Nigerian courts of record — including the Federal High Court — possess **inherent jurisdiction** to set aside their own judgments or orders in appropriate circumstances. This power is not unlimited but is firmly rooted in the need to uphold justice, jurisdiction, and constitutional imperatives such as fair hearing under Section 36 of the 1999 Constitution (as amended).Key grounds for setting aside a judgment by the same court include:
– Breach of fair hearing or failure to join necessary parties: As in this NDC/PMP case, where proceedings were conducted without hearing all interested parties, rendering the judgment a nullity. A judgment obtained in violation of natural justice principles is void *ab initio* and can be set aside.
– Lack of jurisdiction, fraud, suppression of material facts, or fundamental procedural defects.
– Default judgments or irregular orders, where court rules (e.g., Federal High Court (Civil Procedure) Rules) explicitly permit setting aside upon proper application.Courts have repeatedly affirmed this inherent power. Any court of record, including the Supreme Court, can set aside its own judgment where there is a fundamental defect going to jurisdiction or competence. A person affected by such a nullity is entitled *ex debito justitiae* (as of right) to have it vacated, and the court may act *suo motu* or on application.

In this instance, Justice Dashen correctly exercised this power. The earlier judgment, delivered without joining or hearing PMP on the logo dispute, could not stand as a valid substantive decision on the merits.

The Latin maxim functus officio (“having performed one’s office”) is central to this discourse. Once a court delivers a final judgment on the merits, it generally becomes functus officio — it has exhausted its jurisdiction over the matter and cannot revisit, review, alter, or sit on appeal over its own decision. This promotes finality in litigation and prevents endless rehearings.However, *functus officio* is not absolute. Nigerian jurisprudence recognizes clear exceptions, particularly where the judgment is a nullity. A court is not functus officio in relation to a void order; it retains the power (and sometimes duty) to set it aside to restore the status quo. This was precisely the situation here: the December 2025 ruling was tainted by denial of fair hearing and non-joinder, making it liable to being vacated.

Other exceptions include statutory provisions in court rules for setting aside default judgments and the court’s inherent jurisdiction to correct injustices arising from its own procedural lapses. Appellate review remains available for dissatisfied parties, but the originating court is not powerless in cases of fundamental irregularity.

Closely related is the **slip rule**, which allows a court to correct accidental slips, clerical mistakes, omissions, or errors arising from accidental slips in its judgment or order — even after becoming *functus officio* for other purposes. This does **not** permit a substantive review or rewriting of the judgment to change its intended meaning or outcome.As defined in cases like Enterprises Bank Ltd v. Aroso, the slip rule is limited to genuine errors that do not alter the substance of what the court intended. It is an exception to strict functus officio but cannot be invoked to cure fundamental defects like fair hearing violations or to rehear the case on the merits. In Justice Dashen’s ruling, this was not a mere slip correction; it was a substantive declaration of nullity due to constitutional defects, falling squarely under the court’s broader inherent powers rather than the narrow slip rule.

By ordering a fresh hearing with all parties, the court has upheld the sanctity of due process in politically sensitive electoral matters. The substantive issues — NDC’s eligibility, logo disputes, and INEC’s registration obligations — remain pending and must now be determined adversarially with full participation.This ruling reinforces several key principles:
1. Necessary party doctrine: Courts must ensure all whose rights or interests may be affected are joined, failing which proceedings risk being voided.
2. Fair hearing as a constitutional imperativ: Breaches render decisions invalid, not merely irregular.
3. Judicial humility and self-correction: Judges are not infallible; the system provides internal mechanisms to rectify grave errors without always resorting to appeals, which can prolong disputes.Critics may argue this creates uncertainty in political party registration processes, especially close to elections. However, prioritizing constitutional due process over expediency is the hallmark of a robust democracy under the rule of law. Parties aggrieved by the fresh proceedings retain full rights of appeal to the Court of Appeal and, ultimately, the Supreme Court.

Justice Isah Dashen acted within established Nigerian legal bounds by vacating the defective earlier judgment. A trial judge’s power to set aside his own ruling is real and well-recognized, particularly for nullities — it is not the exclusive preserve of the Supreme Court. *Functus officio* protects finality but yields to justice where fundamental rights or jurisdictional defects are at stake. The slip rule offers a limited safety valve for clerical errors but does not apply to the core issues here.This episode serves as a timely reminder that Nigerian courts, while striving for efficiency and finality, must never sacrifice natural justice. As the substantive suit restarts, all parties — INEC, NDC, and PMP — deserve their day in court. The legal desk will continue to monitor developments in this and similar cases.

NNH Op-Ed Legal Desk provides independent analysis of Nigerian legal and constitutional issues. Views expressed are for educational and informational purposes.