Documents Provided to an Expert – Have You Waived Privilege?

This update was co-authored by Jonathan O’Connor, Law Graduate

Part of the recent decision of Justice Tottle in Westgem & Ors v Commonwealth Bank of Australia & Ors (No 2) [2018] WASC 71 illustrates that the legal professional privilege attached to documents provided to an expert for the purposes of producing a report, can be waived when that report is provided to the other party.

Factual background

The expert was instructed by the defendants’ solicitors to produce a report for trial expressing his opinion on questions relating to the time and costs involved in completing the construction of a well-known inner-city development and on the conduct of the superintendent appointed under the building contract.

He was provided with numerous documents, some of which were redacted to conceal privileged material and others which were in unredacted form. Some of the documents provided to the expert in unredacted form were only provided to the plaintiffs in redacted form on the basis of legal professional privilege. The plaintiffs’ application, amongst other things, sought production of these documents in unredacted form.

The expert explained by way of a letter, that he did not rely on any of the privileged documents in the formation of his opinion, nor had the documents influenced the content of his report. The defendants relied on this statement to resist the plaintiffs’ application for production. The plaintiffs argued that irrespective of the expert’s stated position, privilege had been waived and they were entitled to the documents in unredacted form.


Justice Tottle concluded that legal professional privilege in the entirety of the redacted documents provided to the plaintiff had been waived when the expert’s report was served on the plaintiffs. In summary, he made this finding because:

  • the defendants’ approach to the disclosure of the documents had a degree of inconsistency. They were taken as willing to waive privilege had the expert relied upon the documents but were notably unwilling had they not been relied upon;
  • the defendants must have considered the documents to be at least potentially relevant to the questions asked of the expert otherwise they would not have been provided to the expert; and
  • there was potential unfairness in denying the other party the right to cross-examine the expert as to whether he was wrong to disregard the documents.

Proceed with caution when instructing an expert in the context of litigation as the legal professional privilege in any documents provided to the expert can be waived by service of the expert’s report on the other party. Perhaps approach your brief to an expert in a way that assumes the other party will see everything.

The information published in this paper is of a general nature and should not be construed as legal advice. Whilst we aim to provide timely, relevant and accurate information, the law may change and circumstances may differ. You should not therefore act in reliance on it without first obtaining specific legal advice.