Appellants Giving Evidence as Expert Witnesses - Briggs

Finally, a warning sounded by the Court in the case of Briggs v Christchurch City Council, where the Court said it was drawing a line in the sand about parties giving expert evidence to the Court in their own cases.

It was a case about the appropriate level of subdivision and development on Banks Peninsula, in which Ms Briggs and Mr Collins had both lodged appeals to the Environment Court.  Ms Briggs, a very experienced planner and landscape architect, and Mr Collins, a very experienced planner, gave evidence in support of their own appeals.

The Court said that the obligation of an expert witness is to give independent evidence, whereas Ms Briggs and Mr Collins were giving evidence in support of their own appeals.  It referred to Clause 2 of the Code of conduct for expert witnesses, which states, "An expert witness is not an advocate for the party who engages the witness."

Having said that, the Court then concluded that Ms Briggs and Mr Collins had prepared their evidence keeping in mind that they are parties giving evidence in their own cause, and had not done anything untoward in the preparation of their evidence.  The Court says that it suspects, although it does not know, that their evidence would have been similar if given for a third party with which they had no involvement.

Even so, the Court was concerned enough about the issue to say:
Our conclusion is that the privilege afforded an expert witness to give opinion evidence is one of some importance.  We recognise that many lay witnesses before the Environment Court give opinion evidence on a range of matters and that this tension is often recognised by the Court in the weight it attributes to a particular witness's evidence.
The Court has reached the view that it needs to draw a line in the sand on this issue given the tendency of lay witnesses to give opinion evidence and experts to give evidence in their own cause from time to time.  We consider that it is inappropriate as a matter of principle for expert witnesses to give evidence as experts in their own case.  At the very least it will mean that little weight should be given to their evidence where there is a conflict with other witnesses.  It also impacts upon the administration of justice because if some parties are allowed to give opinion evidence in their own cause, they may be seen as getting preferential treatment before the Court compared with other parties.
We accept that the issue has been left unresolved in the past although the purpose of the Practice Note as it relates to expert witnesses clearly seeks in part to address this type of issue.

As was acknowledged by the Court, the approach to this issue taken in this case differs from what has been considered acceptable in the past.  One of the seminal and oft-cited cases in RM law, Nugent Consultants Ltd v Auckland City Council [1996] NZRMA 481, involved planner Denis Nugent giving expert planning evidence in support of a submission lodged by the firm in which he was a principal.  His position was not the subject of any adverse comment by the Court in that case.

However, the Code of Conduct for Expert Witnesses has been introduced, through the Practice Note, since the judgment in Nugent.  Given the warning by the Court in this case, it appears that it would not be prudent for a party in future Environment Court hearings to give expert opinion evidence in his or her own case, as that evidence may be given very little weight, or even ruled inadmissible.  This will apply to section 274 parties as well as to appellants.