9. […] Where the Prosecution is appealing, the Appeals Chamber will reverse only if it finds that no reasonable trier of fact could have failed to make the particular finding of fact beyond reasonable doubt and the acquittal relied on the absence of this finding.[1] […]

13. The ICTR Appeals Chamber in Rutaganda and Bagilishema held that the same standard of reasonableness and the same deference to factual findings of the Trial Chamber apply when the Prosecution appeals against an acquittal. The Appeals Chamber will only hold that an error of fact was committed when it determines that no reasonable trier of fact could have made the impugned finding.[1] Under Article 25(1)(b) of the Statute, the Prosecution, like the accused, must demonstrate “an error of fact that occasioned a miscarriage of justice”. For the error to be one that occasioned a miscarriage of justice, it must have been “critical to the verdict reached”.[2] Considering that it is the Prosecution that bears the burden at trial of proving the guilt of the accused beyond a reasonable doubt, the significance of an error of fact occasioning a miscarriage of justice is somewhat different for a Prosecution appeal against acquittal than for a defence appeal against conviction. An accused must show that the Trial Chamber’s factual errors create a reasonable doubt as to his guilt. The Prosecution must show that, when account is taken of the errors of fact committed by the Trial Chamber, all reasonable doubt of the accused’s guilt has been eliminated.[3]

9. With regard to allegations of errors on a question of law, the Appeals Chamber considers that the standards of review are the same for the two types of appeal: following the example of a party appealing against conviction, an appeal by the Prosecution against acquittal, which alleges that the Trial Chamber committed an error on a question of law, must establish that the error invalidates the decision.

10. With regard to errors of fact in appeals against conviction, the Appeals Chamber applies the standard of the “unreasonableness” of the impugned finding. The Appeals Chamber must determine whether the finding of guilt beyond reasonable doubt is one which no reasonable tribunal of fact could have reached, it being understood that the Appeals Chamber can only overturn a decision of the Trial Chamber where the alleged error of fact occasioned a miscarriage of justice. An appellant who alleges an error of fact must therefore show both the error that was committed and the miscarriage of justice resulting therefrom.[1]

[…]

13. The same standard of unreasonableness and the same deference to factual findings of the Trial Chamber apply when the Prosecution appeals against an acquittal. Thus, when considering an appeal by the Prosecution, as when considering an appeal by the accused, the Appeals Chamber will only hold that an error of fact was committed when it determines that no reasonable trier of fact could have made the challenged finding.

14. Under Article 24(1)(b) of the Statute, the Prosecution, like the accused, must demonstrate “an error of fact that occasioned a miscarriage of justice.” For the error to be one that occasioned a miscarriage of justice, it must have been “critical to the verdict reached.”[2] Because the Prosecution bears the burden at trial of proving the guilt of the accused beyond a reasonable doubt, the significance of an error of fact occasioning a miscarriage of justice is somewhat different for a Prosecution appeal against acquittal than for a defence appeal against conviction. An accused must show that the Trial Chamber’s factual errors create a reasonable doubt as to his guilt. The Prosecution faces a more difficult task. It must show that, when account is taken of the errors of fact committed by the Trial Chamber, all reasonable doubt of the accused’s guilt has been eliminated.

See also paras. 8, 11-12.