Land and Environment Court of NSW

Expert witness code of conduct and duties

Expert witness code of conduct

Expert to comply with code

An expert witness must comply with the code of conduct in Schedule 7 to the Uniform Civil Procedure Rules 2005 (“UCPR”) r 31.23(1). An expert’s report and oral evidence may not be received in evidence unless the expert acknowledges that he or she has read the code of conduct and agrees to be bound by it (UCPR r 31.23(3) and (4)). 

The expert witness code of conduct imposes: 

  • a general duty to the Court
  • a duty to comply with orders
  • a duty to work co-operatively with other expert witnesses
  • requirements regarding the content of the expert’s report.

General duty to the Court

An expert witness has an overriding duty to assist the Court impartially on matters relevant to the expert witness’s area of expertise (UCPR Sch 7 cl 2(1)). An expert witness’ paramount duty is to the Court and not to any party in the proceedings (including the person retaining the expert witness (UCPR Sch 7 cl 2(2)). An expert witness is not an advocate for a party (UCPR Sch 7 cl 2(3)).

Duty to comply with Court directions

An expert witness must abide by any direction of the Court (UCPR Sch 7 cl 5).

Duty to work co-operatively with other expert witnesses

An expert witness, when complying with any direction of the Court to confer with another expert witness or to prepare a parties’ expert’s report with another expert witness in relation to any issue:

(a) must exercise his or her independent, professional judgment in relation to that issue

(b) must endeavour to reach agreement with the other expert witness on that issue

(c) must not act on any instruction or request to withhold or avoid agreement with the other expert witness (UCPR Sch 7 cl 6).

Content requirement for experts’ reports

An expert’s report must (in the body of the report or in an annexure to it) include the following:

(a) the expert’s qualifications as an expert on the issue the subject of the report

(b) the facts, and assumptions of fact, on which the opinions in the report are based (a letter of instructions may be annexed)

(c) the expert’s reasons for each opinion expressed

(d) if applicable, that a particular issue falls outside the expert’s field of expertise

(e) any literature or other materials utilised in support of the opinions

(f) any examinations, tests or other investigations on which the expert has relied, including details of the qualifications of the person who carried them out

(g) in the case of a report that is lengthy or complex, a brief summary of the report (to be located at the beginning of the report) (UCPR Sch 7 cl 3(l)).

If an expert witness who prepares an expert’s report believes that it may be incomplete or inaccurate without some qualification, the qualification must be stated in the report (UCPR Sch 7 cl 3(j)). If an expert witness considers that his or her opinion is not a concluded opinion because of insufficient research or insufficient data or for any other reason, this must be stated when the opinion is expressed (UCPR Sch 7 cl 3(k)).

If an expert witness changes his or her opinion on a material matter after providing an expert’s report to the party engaging him or her (or that party’s legal representative), the expert witness must forthwith provide the engaging party (or that party’s legal representative) with a supplementary report to that effect (UCPR Sch 7 cl 4).

An expert witness must disclose in his or her expert’s report any arrangements under which the charging of fees or costs by the expert witness is contingent on the outcome of the proceedings or the payment of any fees or costs to the expert is to be deferred (UCPR r 31.22(1)). The Court may direct disclosure of the terms of the expert witness’s engagement (UCPR r 31.22(2)).

Court control over giving of expert evidence

Court rules emphasise that the Court retains control over the giving of expert evidence (eg UCPR r 31.17(a) ). This is necessary to ensure integrity of the evidence, proportionality and the just, quick and cheap resolution of the real issues in proceedings.

Last updated:

08 May 2023

Was this content useful?
We will use your rating to help improve the site.
Please don't include personal or financial information here
Please don't include personal or financial information here
Top Return to top of page Top