Originally from Take the Witness: Cross-Examination in International Arbitration, 2d Ed.

The business of preparing a witness for cross-examination begins with the very first encounter between counsel and the prospective witness. Counsel should be conscious from the outset that his manner of dealing with the witness, his calm aura of professional competence, his command of the issues and the relevant documents, is likely to have an impact on the self‑confidence, the ease, and general demeanor of the witness when, weeks or months later, he undergoes cross-examination. Counsel will also be conscious of the possibility that his discussions with the witness may themselves be the subject of inquiry on cross-examination.  In short, everything that counsel does and says in the presence of a potential witness should be designed to assist the witness in responding confidently, coherently, credibly and, above all, truthfully to the questions that eventually will be put to him. 

The matter of truthfulness requires special emphasis. The business of preparing witnesses to testify is viewed by many with skepticism and by some with cynicism. European lawyers and arbitrators, trained in the civil law, are likely to harbor considerable doubt about what is for them the unfamiliar business of horseshedding

witnesses. That doubt, whether or not warranted, can prompt them to credit any suggestion that the testimony they hear is the product of counsel’s inappropriate influence on the witness.  Even across the Channel, in the homeland of the common law, the so‑called Woolf reforms and other developments indicate a heightened uneasiness about the influence of counsel on the testimony of witnesses, and that uneasiness is likely to affect the mindset of barristers serving as arbitrators as they evaluate the written and oral testimony of both percipient and expert witnesses. The extent to which these concerns have thus far had much real impact on international arbitration is not clear to me.  But the American lawyer needs to be conscious of a drift in sentiment and will be prudent to maintain a scrupulosity of the highest order in carrying out the inescapable task of assisting witnesses to fulfill their proper function.