Expert Evidence

Expert evidence is evidence given by a professional or expert witness to assist the Court in a case.

The Expert's Affidavit evidence should be set out in a particular format that confirms with the decision of Makita (Australia) Pty Limited v Sprowles 2001 52 NSWR 705 (Heydon JA) - Mr Justice Heydon now a High Court Judge put forward six requirements for the admissibility and proper receipt of expert evidence in proceedings. Heydon JA summaries the position at page 85 of the judgment as to the admissibility of evidence tendered as expert evidence:

(a) It must be agreed or demonstrates that there is a field of 'specialised knowledge';

There must be an identified aspect of that field in which the witness demonstrates that by reason of specified training, study or experience, the witness has become an expert;

(c) The opinion proferred must be 'wholly or substantially based on the witness expert knowledge';

(d) So far as the opinion is based on facts 'observed' by the expert, they must be identified and admissibly proved by the expert, and so far as the opinion is based on 'assumed' or 'accepted' facts, they must be identified and proved in some other way.

(e) It must be established that the facts on which the opinion is based form a proper foundation for it; and

(f) The opinion of an expert requires demonstration or examination of the scientific or other intellectual bases of the conclusion reached; that is, the expert's evidence must explain how the field of 'specialised knowledge' in which the witness is expert by reason of 'training, study or expertise', and on which the opinion is 'wholly or substantially based' , applies to the facts assumed or observed so as to produce the opinion pronounced.