Former Deputy President Rigathi Gachagua has asked the Supreme Court to throw out a petition filed by the National Assembly challenging the Court of Appeal’s finding that Deputy Chief Justice (DCJ) Philomena Mwilu had no authority to form a judicial bench to hear petitions on his impeachment.

Mr Gachagua filed the application alongside a cross-appeal after Parliament escalated the dispute to the country’s highest court, seeking to overturn the appellate court’s decision delivered in May 2025.

In his court papers, Mr Gachagua accuses the National Assembly of abusing the judicial process and undermining the integrity of the Supreme Court by taking contradictory positions on the same legal question — the DCJ’s powers to assign judges and expand benches under Article 165(4) of the Constitution.

According to his lawyers Dudley Ochiel and Kamotho Njomo, the National Assembly previously argued — and benefited from — the position that the DCJ lacked such powers.

 In 2021, Parliament obtained stay orders in a separate case concerning the dissolution of Parliament on grounds of failing to implement the two-thirds gender rule based on the very argument it now seeks to dismiss.

“Parties are bound by their pleadings. The doctrine of judicial estoppel — the preclusion of inconsistent positions — bars parties from asserting different positions to suit a case. The National Assembly is barred from asserting an inconsistent position on the DCJ’s power under Article 165(4) of the Constitution,” the lawyers state.

They accuse Parliament of engaging in “fast, loose, and cynical gamesmanship” with the courts, shifting positions whenever politically expedient.

For five years, they note, the National Assembly enjoyed stay orders that froze action on retired Chief Justice David Maraga’s advisory to the President to dissolve Parliament for non-compliance with the gender rule.

“For self-interest, the National Assembly plays a cynical game with the court by shifting its interpretation of the law. This change of position constitutes a fraud on the court and would undermine proceedings at the apex court,” the lawyers add.

Mr Gachagua wants the Supreme Court to apply the doctrine of judicial estoppel to prevent the National Assembly from reversing its stance, arguing that litigants who contradict themselves in related matters erode public trust in the administration of justice.

He is seeking a summary dismissal of the appeal for violating this doctrine, abusing the court process and undermining the Supreme Court’s authority.

In addition, he is asking the Supreme Court to suspend ongoing High Court proceedings tied to his impeachment until his cross-appeal is resolved.

His application targets the three-judge bench — Justices Eric Ogolla, Anthony Mrima, and Fredah Mugambi — assigned by Ms Mwilu to hear the Kerugoya petitions in October 2024.

 The bench later lifted the conservatory orders that had halted his replacement as Deputy President.

Mr Gachagua insists the bench lacked jurisdiction to act on the petitions and that the Court of Appeal erred by failing to order a reconstitution consistent with judicial practice where matters are remitted to a lower court with fresh judges.

He warns that without a temporary stay, any successful appeal or cross-appeal could be rendered meaningless.

His lawyers are also challenging the inclusion of certain documents by the National Assembly in its appeal, claiming they were “sneaked in” without permission and were not part of the High Court or Court of Appeal records.

They allege Parliament is attempting to “patch up weak points” in its case and fill gaps in the evidence.

The contested documents include letters, dated October 18, 2024 purportedly from the Judiciary and the Office of the Chief Justice, stating that Ms Mwilu had appointed the bench.

Mr Gachagua’s legal team says allowing the documents would be prejudicial and disproportionate, outweighing any potential benefit to the case.

In its appeal, the National Assembly is defending the DCJ’s actions, arguing that both the Constitution and the Judicial Service Act allow her to empanel benches when deputizing the Chief Justice.

It faults the Court of Appeal for restricting the DCJ’s powers to instances where the Chief Justice is electronically unreachable, medically incapacitated, or legally unable to perform her functions.

According to Parliament, such a limitation effectively rewrites the Constitution by introducing conditions not found in the supreme law.

 It argues that inability to act can arise from a variety of legitimate circumstances — technical, personal, or operational — that do not require public disclosure.

The Court of Appeal in its ruling had concluded that there was no indication Chief Justice Martha Koome was electronically unreachable or physically unable to perform her administrative duties when the Kerugoya petitions arose.

The court held that, in the absence of such incapacity, the DCJ could not step in to empanel the bench.

The National Assembly now wants the Supreme Court to overturn that reasoning, insisting that the DCJ was acting within her constitutional mandate to deputize the Chief Justice under Article 163(1)(b).

“The Constitution, as the supreme law, imposes no such restrictive conditions on the functions of the Deputy Chief Justice. By imposing a non-existent standard of “electronic availability” the Court of Appeal effectively amended the Constitutional framework through judicial interpretation,” says the National Assembly, through G&A Advocates LLP, in the court papers.

The case is expected to be heard once the Supreme Court judges return from vacation.