At present the New South Wales, Queensland, South Australia and Western Australia Solicitors’ Rules require the return of documents to an opponent where there is inadvertent disclosure of confidential documents. The High Court recently commented that such a rule should not be necessary as “in the not too distant past it was understood that acting in this way obviates unnecessary and costly interlocutory applications” (Expense Reduction Analysts Group Pty Ltd v Armstrong Strategic Management and Marketing Pty Limited (2013) 303 ALR 199 (“ERA v Armstrong”))
In ERA v Armstrong a firm of solicitors, Norton Rose, gave general discovery on behalf of a client. This included 13 documents that the client intended to claim privilege over, but which were inadvertently listed as non-privileged and produced for inspection. The error appeared to result from a mistake in the process of reviewing and identifying documents in large-scale discovery. On receipt of the documents Marque Lawyers sent a letter to Norton Rose stating that there was an inconsistency in the discovery as some communications were disclosed, but others were the subject of a claim for privilege. Norton Rose wrote to Marque Lawyers stating that the production was a mistake and requested the documents be returned. Marque Lawyers refused to return the documents and said that any privilege attaching to them had been waived.
Marque Lawyers was successful in the New South Wales Supreme Court and Court of Appeal. On appeal the High Court of Australia unanimously ordered the return of the documents to Norton Rose. The High Court noted that times have changed since the decision of Slade LJ in Guinness Peat Properties Ltd v Fitzroy Robinson Partnership  1 WLR 1027 at 1044. and case management concerns, including specific case management powers in the rules (in ERA v Armstrong, the CPA NSW ss 56, 57, 58 and 59) now give courts the power to order the return of the documents to further the “overriding purpose”, that is, the just, quick and cheap resolution of the real issues in the dispute or proceedings (ERA v Armstrong, , ). The High Court considered the pursuit of satellite interlocutory proceedings, in circumstances where the discovery dispute was a minor issue and offered very little advantage to the recipient, would not fulfill the overriding purpose and is the kind of conduct to be avoided (ERA v Armstrong, ). Also, a mistake had been made and this fact was not disputed. As such, there was no question of waiver sufficient to be agitated, and it was necessary that the mistake be corrected and the parties continue with their preparation for trial (ERA v Armstrong,  - ).