20. The Appeals Chamber considers that Hategekimana’s submissions are based on the erroneous premise that legal officers play a controlling role in judicial decision-making.[1] The Appeals Chamber has previously held that “[j]udicial decision-making is the sole purview of the Judges and legal officers […] play no role in it.”[2] The Appeals Chamber further considers that “mere assertions to the effect that a staff member may influence a Judge during deliberations or the adjudication process are not a sufficient basis, in and of themselves”,[3] to create in the mind of a reasonable observer, properly informed, an appearance of bias or to rebut the presumption of impartiality of judges. The Appeals Chamber does not find that the role of the legal officer in the competition is “so problematic” as to impugn the impartiality of the Judges or the appearance thereof.[4] Therefore, there is no merit to Hategekimana’s contention that the Trial Chamber erred in allowing the legal officer to be involved in the drafting process of the Trial Judgement.

9.       The Appeals Chamber recalls that legal officers assisting Judges at the Tribunal are not subject to the same standards of impartiality as the Judges of the Tribunal, and that judicial decision-making is the sole purview of the Judges.[1] Legal officers merely provide assistance to the Judges in legal research and preparing draft decisions, judgements, opinions, and orders in conformity with the instructions given to them by the Judges.[2]

10.     Notwithstanding the above, in some cases, a prospective staff member’s statements or activities may be so problematic as to either impugn the perceived impartiality of the Judges or the appearance thereof, or, even if this were not the case, the Tribunal’s fundamental guarantees of fair trial.[3] In this respect, the Appeals Chamber recalls in particular, that an unacceptable appearance of bias exists, inter alia, where the circumstances would lead a reasonable observer, properly informed, to reasonably apprehend bias.[4] The Appeals Chamber further recalls that there is a presumption of impartiality which attaches to the Judges of the Tribunal and which cannot be easily rebutted.[5]

[…]

37.     When addressing whether the impartiality of the Judges in this case could be affected by the Impugned Staff’s involvement in the Karadžić case, the Trial Chamber found that, even though “there is a considerable degree of overlap between the Karadžić case and the present case”, “a properly informed and reasonable observer would not consider […] that the judges in the present case ha[ve] failed to maintain the high degree of integrity and impartiality to which they are sworn, even if they or the Impugned Staff had worked on both cases.”[6] It added that a properly informed and reasonable observer would not expect that the Judges in this case would do anything other than rule fairly on the issues before them, relying exclusively on the evidence adduced in the present case, even if they or their staff had been exposed to evidence in both cases.[7] The Trial Chamber concluded that the presumption of impartiality attached to the Judges in this case had not been rebutted on the basis that the Impugned Staff had worked on an overlapping case in which factual findings were made in relation to Mladić.[8]

38.     With respect to Mladić’s argument that the Trial Chamber failed to sufficiently reason its conclusions relating to the application of the reasonable observer test,[9] the Appeals Chamber considers that Mladić’s arguments effectively amount to a challenge to how the reasonable observer test has been interpreted in the case law. The Appeals Chamber is of the view that Mladić’s argument reflects his disagreement with the jurisprudence relied upon by the Trial Chamber and set out in detail in the applicable law section of the Impugned Decision,[10] as well as with the Trial Chamber’s reliance on this jurisprudence when assessing whether the Impugned Staff’s involvement in the Karadžić case could lead to an appearance of bias of the Judges in this case[11] without explaining how the Trial Chamber erred in following this case law. The Appeals Chamber finds that Mladić fails to demonstrate an error in the Trial Chamber’s reasoning.

39.     Moreover, the Appeals Chamber recalls that “‘mere assertions to the effect that a staff member may influence a Judge during deliberations or the adjudication process are not a sufficient basis, in and of themselves’, to create in the mind of a reasonable observer, properly informed, an appearance of bias or to rebut the presumption of impartiality of judges.”[12] Accordingly, the Appeals Chamber does not consider that a staff’s previous work on an overlapping case is, in and of itself, sufficient to impugn the Judges’ impartiality or the appearance thereof. The Appeals Chamber therefore finds no merit to Mladić’s argument that a reasonable observer would consider that the fact that the Impugned Staff previously worked on the closely-related Karadžić case, is sufficient to rebut the impartiality of the Judges in this case.

See also paragraphs 30, 33.

[A] Legal Officer and the then President of the Tribunal […] cannot be subpoenaed to testify as witnesses on matters relating to their official duties or functions because their work is integral to the operation of the Tribunal which must be protected by confidentiality. […]