It is believed that this pointed questioning of their assertions is a good way to determine if witnesses have really told the truth, the whole truth and nothing but the truth, or if they exaggerated, embellished their testimony or, even worse, lied. This presumption helps us determine the outcome of borderline cases, where some doubt still remains even after hearing all the evidence. It is not only in the criminal trial system that such care is taken in the initial assessment process of the information at hand. In fact, many systems operate just about the same way. For instance, tests are administered to determine if someone is competent to drive a car or to practice medicine.
Banks carry out credit checks before they lend money.
Financial consultants conduct market research before launching a new product. Large corporations must often undertake environmental impact studies before proceeding with the construction of new production facilities. However, even if we do our best in trying to get the best information possible, we can still make mistakes. We can never be sure that the system we use, however well managed it may be, works perfectly every time. The Law Commission of Canada has recently sponsored a research project to study issues relating to the way decision-making entities operate to determine if their processes could be improved.