Officiële Toelichting

P-16A ‘Relevant’ evidence is probative material that supports, contradicts, or weakens a contention of fact at issue in the proceeding. A party should not be permitted to conduct a socalled ‘fishing expedition’ to develop a case for which it has no support, but an opposing party may properly be compelled to produce evidence that is under its control. These Principles thereby permit a measure of limited ‘discovery’ under the supervision of the court. Nonparties are in principle also obliged to cooperate.

P-16B In some legal systems the statements of a party are not admissible as evidence or are accorded diminished probative weight. Principle 16.1 accords a party's testimony potentially the same weight as that of any other witness, but the court in evaluating such evidence may take into account the party's interest in the dispute.

P-16C Under Principle 16.2, the requesting party may be required to compensate a nonparty's costs of producing evidence.

P-16D In some systems, it is generally a violation of ethical or procedural rules for a lawyer to communicate with a potential witness. Violation of this rule is regarded as ‘tainting’ the witness. However, this approach may impede access to evidence that is permitted in other systems and impair a good preparation of the presentation of evidence.

P-16E The physical or mental examination of a person may be appropriate when necessary and reliable and its probative value exceeds the prejudicial effect of its admission.

P-16F According to Principle 16.4, eliciting testimony of parties, witnesses, and experts should proceed as customary in the forum, either with the parties conducting the primary examination or with the judge doing so. In any event, a party should have the right to conduct supplemental questioning by directly addressing another party or witness. The right of a party to put questions directly to an adverse party or nonparty witness is of first importance and is now recognized in most legal systems. Similarly, a party should be permitted to address supplemental questions to a witness, including a party, who has initially been questioned by the court.

P-16G Principle 16.6 signifies that no special legal value, positive or negative, should be attributed to any kind of relevant evidence, for example, testimony of an interested witness. However, this Principle does not interfere with national laws that require a specified formality in a transaction, such as written documentation of a contract involving real property.

P-16H Sanctions may be imposed against the failure to produce evidence that reasonably appears to be within that party's control or access, or for a party's failure to cooperate in production of evidence as required by the rules of procedure. See Principles 17 and 21.3.

P-16I There are special problems in administering evidence in jury trials, not covered by these Principles.