All witnesses for the prosecution and the defence are potential sources of information and may prove valuable to defence counsel. It has long been settled that there is no property in a witness and that a witness may be interviewed by both sides.
Of course, a lawyer wants to avoid the possibility of unwittingly becoming a witness and should therefore ideally have all witnesses interviewed by someone else, preferably an independent private investigator who may be called in the event that the witness later gives evidence inconsistent with any statement earlier provided. The importance of preserving in some independent fashion the previous oral and written statements of witnesses is highlighted by the various uses that may be made of previous statements under sections 9, 10, and 11 of the Canada Evidence Act.
The importance of the preparation of witnesses cannot be overstated. Most cases, in fact, turn on the performance of the witnesses. But there is no foolproof formula or method to prepare witnesses for trial. They come to us in all types and fashions, and many are, to say the least, a challenge. Some communicate easily and well, others only grudgingly and in monosyllabic grunts. Patience and preparation are all.
Witness preparation, difficult as it may be, is the first important step to changing the level of your success at trial.
We want our witnesses to be poised and confident and to possess great nimbleness of mind. The best way to approximate this ideal state, once all the facts have been gathered, assimilated, and represented in your trial brief, is to subject all potential witnesses, including experts, to an interview process no less rigorous than that of a cross-examination by a skilful prosecutor. The exercise will pay dividends because it familiarizes the witness with an important part of the trial experience and demystifies the process of cross-examination, calming the witness’s fears.