As a general rule, international courts admit probative evidence. But leaked files, although potentially probative, are often a different story. And while no party has proffered the recently leaked Panama Papers in an international hearing quite yet, the proffer is likely to be inevitable. The ICJ has procedural and evidentiary rules that do not necessarily follow stare decisis principles, instead blending and balancing civil and common law approaches.
When the papers are ultimately presented, the question is likely to be whether the files meet established standards of relevance, reliability, and authenticity — particularly whether the files show up in recent raids of Mossack Fonseca’s offices (or future ones, for that matter).
It is possible for evidence collected by hazy means to be admissible in international courts. In the Corfu Channel case, the ICJ admitted evidence obtained during a mine-sweeping operation conducted by the British Navy while their vessels were in violation of Albanian territorial waters. However, some may find the facts in Corfu Channel distinguishable from matters involving leaked documents. In addition, more recent rulings tend to be less favorable, particularly when a party proffers leaked documents.
In its Decision on the Admissibility of Documents Published on the WikiLeaks Website, the Special Tribunal for Lebanon’s Appeals Chamber ruled that evidence is considered relevant if it relates to the testimony that will be heard by the tribunal, but nevertheless held that because the leaked documents at issue were not acknowledged by the state from which they allegedly originated, they could not be properly authenticated. The Appeals Chamber in Wikileaks noted that the Extraordinary Chambers in the Courts of Cambodia ruled and reasoned similarly with respect to a defendant’s proffer of WikiLeaks documents in Decision on the co-prosecutors’ and Khieu Sampan’s Internal Rule 87(4) requests concerning US diplomatic cables. It is likely, however, that these cases can be distinguished with respect to the Panama Papers, because their source is Mossack Fonseca, a private firm, and not a state agency or instrumentality.
Moreover, the International Criminal Court [ICC], the International Criminal Tribunal for the former Yugoslavia, [ICTY] and the International Criminal Tribunal for Rwanda [ICTR] have established rules of evidence requiring the satisfaction of minimum standards of relevance, reliability, and authenticity. In the Lubanga case, the ICC held that indicia of reliability with respect to evidence include the source of the evidence and the chain of custody. Here, both are potentially at issue if not corroborated by government searches, but that is not an insurmountable obstacle, so long as the document “is what it professes to be in origin and authorship.” Pursuant to the ICTR’s holding in Prosecutor v. Karemera, a court may properly authenticate digital evidence by corroborating it through external indicators, it is possible that an international tribunal such as the ICJ would find sufficient indicia of reliability to admit the evidence under the Corfu Channel standard.
Because the Panama Papers involve heads of state and those close to them, it is likely that their release will serve as a defining moment for the determination of proper standards of admissibility, unless the ICJ dodges the question by piggybacking the leaked documents’ authenticity on sovereign states’ independent seizures and investigations. Even then, the Papers’ proffer before the ICJ will likely lead to a landmark decision.