79. Every person is competent as a witness unless the judge advocate finds that he is incapable of

• (a) communicating his evidence so as to be understood by the court, whether by expressing himself directly, through interpretation by a person who can understand him or in any other manner; or

• (b) understanding the duty of a witness to tell the truth.

• 80. (1) Subject to subsection (2), a witness may testify only to relevant matters that he has perceived with his own senses.

• (2) A witness may testify to matters that he has not perceived with his own senses when permitted to do so under Part III, or under section 82.

81. A witness is an expert witness and is qualified to give testimony if the judge advocate finds that

• (a) to perceive, know or understand the matter concerning which the witness is to testify requires special knowledge, skill, experience or training;

• (b) the witness has the requisite knowledge, skill, experience or training; and

• (c) the expert testimony of the witness would substantially assist the court.

• 82. (1) For the purposes of this section, “graphic medium” means a model, map, diagram, photograph or other pictorial or graphic mode of description and includes a record of data, experience, communications or events made by accurate mechanical, electrical or other scientific methods.

• (2) Subject to subsections (3), (4) and (5), testimony may be given or supplemented by a graphic medium.

• (3) A graphic medium shall be presented as part of the testimony of a witness who has sufficient knowledge of the facts represented to prove that the graphic medium used does accurately represent them.

• (4) A photograph or other mode of depicting facts, made with scientific apparatus that is capable of disclosing data not perceivable by the unaided senses, may be admitted as part of the evidence of a witness who can prove that the apparatus was of a standard make, in good condition and used by a competent operator.

• (5) If proved to be trustworthy, a mechanical, electrical or other device may be employed to display or render audible to the court the data, experience, communications or events recorded by a graphic medium admitted under this section.

• 83. (1) When evidence is given by a person who may be an accomplice, the judge advocate shall

  • (a) instruct the court as to what in law makes a person an accomplice;

  • (b) direct the attention of the court particularly to the facts in evidence implicating the witness in the offence charged; and

  • (c) submit to the court the issue as to whether or not the facts implicating the witness would make him an accomplice.

• (2) Subject to the directions given in connection with sections 85 and 86, if the only evidence against the accused is that given by a witness who may be an accomplice, the judge advocate shall, either

  • (a) instruct the court that, if it concludes that the witness was at any stage an accomplice in the offence charged, there is danger of injustice in convicting the accused of that offence upon the evidence of the apparent accomplice standing alone and uncorroborated, but it is at liberty to do so; or

  • (b) advise the court not to convict on the uncorroborated evidence of the apparent accomplice, but that it is at liberty to do so if it chooses.

• (3) The evidence of one accomplice is not corroborative of the evidence of another accomplice.

• (4) Subject to statutory provisions as to corroboration or the number of witnesses necessary for conviction, if the court considers an accomplice to be a credible witness his evidence may of itself be sufficient for a conviction.