After the witnesses have been heard, the party or parties must be given an opportunity of making observations. The observations may be made either in oral proceedings following the taking of evidence or exceptionally in writing after transmission of the minutes of the taking of evidence. The decision on this matter will rest with the competent department. The parties may file requests accordingly.
Only when this has been done may the competent department proceed to evaluate the evidence. Where a witness's testimony which is crucial to the decision has been challenged by a party but the department regards it as credible, or where a witness's oral or written testimony is disregarded in its decision as being not credible, the department concerned must state the grounds for its view in its decision.
In evaluating a witness's oral or written testimony, special attention is to be paid to the following:
Apparent contradiction in the testimony of witnesses may sometimes be resolved in this way. For example, a close examination of apparently contradictory statements by witnesses as to whether a substance X was commonly used for a particular purpose may show that there is in fact no contradiction at all, in that while one witness was saying specifically that substance X was not used for that particular purpose, the other witness was saying no more than that substances like X, or a certain class of substances to which X belonged, were commonly used for this particular purpose without intending to make any statement regarding substance X itself;
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/e_iv_4_5.htm
Date retrieved: 17 May 2021