witnesses and their clients and lawyers, as well as the risk of such communications being subject to disclosure, have been extensively discussed in the legal media. As any experienced expert involved in Australian disputes would attest, lawyers are particularly cautious when it comes to communications with retained experts to avoid waiver of privilege. In my experience, lawyers have sometimes operated on the assumption that all communications between the expert and lawyer could be subject to disclosure, to a point of forbidding any communications of advice or draft reports prior to the issue of the final expert report, permitting oral communications only. Privilege issues may occur where a clean expert provides strategic advice at an early stage in the dispute. For example, if a clean expert provides an impartial opinion to a client on mitigation measures that should be taken to control costs, such advice may be subject to disclosure. If the client does not actually follow such advice, the clean expert may be put in a difficult position when opining on whether costs are reasonable in their expert report. There may also be situations where a clean expert’s early involvement in the formulation of the claim could be seen to taint the impartiality of their evidence. However, the appointment of a dirty expert may avoid such issues since, as I understand it, the dirty expert could be considered part of the legal team advocating for the client and it may be arguable that communications between the lawyers and the dirty expert are therefore subject to privilege. Are thereany significant drawbacks to this strategy? I suppose the most significant drawback of appointing two experts is the additional expense. However, it seems to me that if the dispute is significant, such fees are outweighed by the advantages mentioned earlier. Another drawback is that in Australia it may be considered as too much of a risk for an expert carrying out a ‘dirty’ role at an early stage in a dispute to subsequently act as the clean expert at a later stage due to the inherent conflict in duties between these roles. Canyou tell us about your ownexperiences acting asbotha ‘dirty’ anda ‘clean’ expert? Ankura provides expert quantum and delay services for both clean and dirty expert roles. I have been involved in quantum expert work for around 20 years after working as a quantity surveyor in professional practice, so I have had my fair 66 WWW.LAWYER-MONTHLY.COM | AUG 2022 EXPERT WITNESS Delay and disruption claims arising from a plethora of events are notoriously difficult to demonstrate.