Key legal question
Whether refusing to hear Dame B. violated the parties' right to be heard and equality of arms in international arbitration.
Extracted holding
No. The tribunal could refuse an evidentiary measure that was manifestly incapable of producing reliable proof because of the witness's documented memory problems and speech difficulties.
Extracted reasoning
The medical certificates showed that her testimony would not credibly contribute to fact-finding. The appellant still had the same procedural opportunities as the other parties, and the refused interrogation was not a required or useful proof measure.