Prosecutors at the International Criminal Court (ICC) have opposed a second attempt by the lawyers of former president Rodrigo Duterte to disqualify two of the three judges hearing his case, citing concerns of impartiality.

The objection followed a renewed appeal by the defense to recuse Judges Reine Alapini-Gansou and María Flores Liera from adjudicating Duterte’s case — a similar motion already turned down by the ICC Pre-Trial Chamber I on 6 May.

Duterte’s lead counsel, Nicholas Kaufman, asserted that the judges “have already predetermined the outcome of the jurisdictional dispute in [their] favour” as they “have had prior involvement in the most substantive legal question in the case against Mr. Duterte.”

The judges, he said, had authorized the investigation into Duterte’s bloody war on drugs prior to the Philippines’ withdrawal from the Rome Statute in March 2019. They were also signatories to the arrest warrant of the erstwhile leader.

However, Deputy Prosecutor Mame Mandiaye Niang dismissed Kaufman's claims of perceived bias as baseless.

He argued that prior rulings made by the judges did not automatically indicate bias in the present case, noting that earlier determinations related to jurisdiction were made before the defense had even submitted their observations.

Niang also contended that prior determinations are preliminary in nature and made for a limited purpose.

“By contrast, the judges in the present case have only ever considered relevant issues in their judicial capacity, as they arise from the matter before them, with all the safeguards that a reasonable observer would apprehend in those circumstances,” Niang said.

Kaufman had insisted that the ICC no longer has jurisdiction over Duterte’s case, given that the Philippines is no longer a member of the Rome Statute—the treaty that established the ICC—since its withdrawal in March 2019.

He asserted that the jurisdictional issues raised between the prior and the present case are not just similar but identical, raising doubts about the judges' impartiality given their direct role in the earlier ruling.

“It is not reasonable to expect a judge who has recently expressed a highly publicised position on a specific legal issue to depart from that view. It is specifically for this reason, so it is submitted, that the Presidency has ruled that an objective observer’s perception of a judge’s inability to diverge from previous rulings on the same issues gives rise to a presumption of partiality,” the motion filed by defense on 12 May read.

The prosecution, however, insisted that judges handling similar legal issues is never unusual, and that prior determinations alone do not demonstrate conflict or impropriety. Niang said Kaufman also fell short in meeting the threshold to rebut the presumption of impartiality.

“Judges of the Court are professional judges and enjoy a presumption of impartiality. As such, the plenary of judges has previously established that the disqualification of a judge ‘is not a step to be undertaken lightly’ and ‘a high threshold must be satisfied in order to rebut the presumption of impartiality’,” he averred.

Moreover, Niang argued that judges adjudicating on jurisdiction more than once is explicitly foreseen and permitted by the Rome Statute.

“As such, article 15(4) of the Statute specifies that, the Pre-Trial Chamber shall authorise the commencement of an investigation if it considers, inter alia, that ‘the case appears to fall within the jurisdiction of the Court’, with the explicit safeguard that this preliminary assessment is ‘without prejudice to subsequent determinations by the Court with regard to the jurisdiction’,” the motion read.

Hence, Niang said, “There is no reason why the judges would not be in a position to objectively evaluate this new, and purely legal in nature, question. No fair-minded and informed observer, having considered all the facts and circumstances, would reasonably apprehend bias on the part of the judges in this case.”

The 80-year-old Duterte has been under the ICC's custody in The Hague since his arrest on 11 March in Manila and will remain there while awaiting the confirmation of his charges scheduled for 23 September.

He faces a single count of crimes against humanity in connection with 43 extrajudicial killings committed between 1 November 2011 and 16 March 2019, spanning his time as mayor of Davao City and as president.

The ICC insists that this period still covers the time when the Philippines was a member of the Rome Statute.