Commonwealth Numbered Regulations Commonwealth Numbered Regulations(1) Evidence of an opinion is not admissible to prove the truth of any matter about which the opinion was expressed unless:
(a) the opinion is based on what the person saw, heard or otherwise perceived about a matter or event, and evidence of the opinion is necessary to obtain an account or understanding of the person's perception of the matter or event; or
(b) the opinion is expressed by a person who has specialised knowledge based on the person's training, study or experience, and the opinion is wholly or substantially based on that knowledge in the context of the facts of the case relevant to the formation of the opinion.
(2) The summary authority is not required to accept the opinion of a person who is presented as having specialised knowledge based on the person's training, study or experience if:
(a) the summary authority is not satisfied that the person has the appropriate training, study or experience; or
(b) the person's opinion is based on assumptions that the summary authority does not find proven; or
(c) the opinion is contradicted by another person who has specialised knowledge based on the person's training, study or experience; or
(d) the opinion is not in accord with other evidence in the case.