As has been widely reported, the English High Court has approved the use of technology assisted review (“TAR”) for discovery, or "disclosure" as the process is now known under the English CPR. The case is of interest because it is the first time that an English court has expressly approved the use of TAR for inter party disclosure, which first received approval in Ireland in March 2015. 

In Pyrrho Investments Ltd v MWB Property Ltd1 a large body of potentially relevant documentation had been deleted and had to be restored from back up tapes, resulting in 17.6 million electronic files, which deduplicated down to 3.1 million electronic files requiring review. The English Civil Procedure Rules require a party making discovery to conduct a reasonable search but the court noted that there is no guidance as to how the search should be conducted, although there is reference in a practice direction to the use of automated search techniques, albeit with a health warning about the risk of “injudicious use” of such techniques.

Master Matthews considered the US case of Moore v Publicis Groupe2 and the decision of Fullam J in IBRC v Quinn.3 He outlined several factors in favour of approving the use of TAR, including the fact that the Irish Commercial Court had approved its use in a case where there was not agreement between the parties. Regarding the accuracy of the technology he emphasised that “there will be greater consistency in using the computer to apply the approach of a senior lawyer towards the initial sample (as refined) to the whole document set, than in using dozens, perhaps hundreds, or lower-grade feeearners, each seeking independently to apply the relevant criteria in relation to individual documents”.

Master Matthews was satisfied that this was a suitable case for the use of predictive coding software but noted that whether it would be suitable for other cases would depend on the particular circumstances of each case.

There are no immediate parallels between the English and Irish procedures in relation to discovery and, for example, the "train of enquiry" relevance requirement no longer applies to standard disclosure in England and Wales, whereas it remains central to Irish discovery procedures. There is also no Irish equivalent of the English “overriding objective” which requires the court to have regard to saving expense and to deal proportionately with the case, although the recently published Commercial Lawyers Association of Ireland Good Practice Discovery Guide v2.0 encourages parties to engage and provides guidance on the use of TAR for inter party discovery.

It should be noted that the Quinn decision is under appeal to the Irish Court of Appeal, which will have to consider whether an appropriately conducted TAR discovery complies with the requirements of order 31 rule 12 of the Rules of the Superior Courts and with Irish law. This will include consideration of the extent to which it is permissible for a party making discovery to manually review only a subset of the overall data set, with sampling and the use of analytical tools, having regard to the volume of documents involved and the cost of conducting a full manual review. It will also include consideration of a protocol proposed by the plaintiffs for the use of TAR and the extent to which the party making discovery must provide the receiving party with access to the predictive coding and its output