OPINION OF THIRD PERSONS WHEN RELEVANT

59. Opinions of experts.  When the Court has to form an opinion upon a point of foreign law or of science, or art, or a stop identify of handwriting or finger impression, the opinions upon that point of persons

specially skilled in such foreign law, science or art, or in question as to identity of hand‑,writing or finger impressions are relevant facts.

Such persons are called experts.

(a) The question is, whether the death of A was caused by poison. The opinion of experts as to the symptoms produced by the poison by which A is supposed to have died, are relevant.

(b) The question is, whether A, at the time of doing a certain Act, was by reason of unsoundness of mind, incapable of knowing the nature of the act, or that he was doing what was either wrong or contrary to law.

The opinions of experts upon the question whether the symptoms exhibited by A commonly show unsoundness of mind, and whether such unsoundness of mind usually renders persons incapable of knowing the nature of the acts which they do, or of knowing that what they do is either wrong or contrary to law, are relevant.

(c) The question is, whether a certain document was written by A. Another document is produced which is proved or admitted to have been written by A.

The opinion of experts on the question whether the two documents were written by the same person or by different persons, are relevant.