Master Matthews approved the use of predictive coding technology. The court identified ten factors in favour of the use of predictive coding in the electronic disclosure process, whilst noting that there were no factors of any weight pointing in the opposite direction. The factors identified by the court were as follows.
Experience in other jurisdictions shows that predictive coding software can be useful in appropriate cases. In the absence of English case law on the application of predictive coding, Master Matthews turned to decisions in other jurisdictions notably, the US Federal Court case of Moore v Publicis Groupe, 11 Civ 1279 (ALC)(AJP) and the Irish High Court case of Irish Bank Resolution Corporation Ltd v Quinn  IEHC 175, both of which had endorsed the use of predictive coding.
There was no evidence to show that the use of predictive coding software leads to less accurate disclosure than manual review alone or keyword searches and manual review combined, and indeed there is some evidence to the contrary.
There will be greater consistency in using the computer to apply the approach of a senior lawyer towards the initial sample to the whole document set, than in using dozens of lower-grade fee-earners, each independently applying the relevant criteria in relation to individual documents.
There is nothing in the CPR or Practice Directions to prohibit the use of such software.
The number of electronic documents which must be considered for relevance and possible disclosure in the present case was huge.
The cost of manually searching these documents would have been enormous, amounting to several million pounds. Therefore a full manual review would be ‘unreasonable’ under Practice Direction 31B where a suitable automated alternative exists.
The cost of using predictive coding software would depend on various factors, including whether the number of documents was reduced by keyword searches. The estimates given in this case varied between £181,988 (plus monthly hosting costs of £15,717), to £469,049 (plus monthly hosting costs of £20,820). In either case, it was considerably less expensive than the alternative of a full manual review.
The ‘value’ of the claims made in this litigation is in the tens of millions of pounds. Therefore the estimated cost of using the software was proportionate.
The trial in the present case is not due to take place until June 2017, so there would be plenty of time to consider other disclosure methods if for any reason the predictive coding software route turned out to be unsatisfactory.
The parties had agreed on the use of the software, and also how to use it, subject only to the approval of the Court.