English court approves use of Technology Assisted Review for disclosure

The ever-growing quantities of electronic documents falling to be reviewed for disclosure in commercial cases raise issues that the courts have not always been willing to grapple with. Despite the E-Disclosure Practice Direction having come into effect on 01 October 2010, the approach to disclosure of electronic documents in litigation is often unsophisticated. The parties commonly identify key individuals’ computers to search and then apply search terms within a date range to limit the number of emails that will be reviewed, a process then undertaken by a team of junior lawyers.

For several years now far more efficient alternatives have been available from eDiscovery platforms such as Relativity. Automatic de-duplication is used by default to weed out multiple copies of the same document. The industry is now embracing a second more advanced level of deduplication, known as email threading which is applied to reduce chains of emails to a single document containing the whole conversation. Our experience to date has shown that this can reduce the number of documents needing human review by up to 75%.

More advanced still is Technology Assisted Review (TAR) or Predictive Coding, where software can be taught to identify relevant documents, enabling the computer to carry out the first level of review. Studies in the US have shown the results to be more consistent and accurate than human review. The cost savings in large scale disclosure exercises can be vast.

TAR works by a computer “learning” how to identify relevant documents through the decisions of a lawyer reviewing sample batches of documents and categorising them. The computer then offers decisions on further batches of documents which the lawyer checks, until a point of accuracy is reached where the computer takes over. Further quality control checks can then be made on documents that the program has categorised as relevant or irrelevant. Eventually a set of relevant documents is produced that represents a fraction of the original data set and which is then subject to human review.

Court endorsement

The US Federal Court approved the use of TAR in 2012 in the case of Moore v Publicis Groupe, while the Irish High Court also endorsed the practice in 2015 in the case of Irish Bank Resolution Corporation Ltd v Quinn. However, until now there was no English court authority approving its use. The case of Pyrrho Investments Ltd v MWB Property Ltd changes that.

In Pyrrho Investments, Master Matthews, an acknowledged expert on disclosure, reviewed the rules on disclosure and approved the use of TAR, making the following points:

• there is nothing in the CPR or Practice Directions to prohibit the use of TAR
• there is no evidence that TAR leads to less accurate disclosure being given than with a manual review
• in cases where the electronic documents number in the millions, a full manual review would be unreasonable within the meaning of the Practice Direction, where TAR could be used, and
• the use of TAR is compatible with the Overriding Objective of the CPR to deal with cases “justly and at proportionate cost.”

Comment

This decision is welcome, as the use of TAR has to some extent been held back by the lack of express judicial approval for its use. In Simmons & Simmons’ experience, the benefits of accuracy and the saving in time and cost which can be offered are substantial. To get the best out of the technology requires an experienced team, like Simmons & Simmons eDiscovery Solutions Team, who can provide advice and guidance as to the breadth and limitations of technology based reviews.

It is notable that the parties were agreed as to the use of TAR in this case, with neither side putting forward arguments against it, meaning that a more adversarial consideration of TAR’s merits may yet be heard by the courts. However, given that the cost of disclosure will ultimately fall upon the losing party, it is in neither side’s interests to resist the most efficient means of doing it. A judgment such as this has been awaited by all those keen to see the cost benefits of technology brought to the English courts (see our article Disputes: What is coming in 2016?) and should allow commercial parties to use TAR with confidence.

Update

A decision of the Commercial Court in October 2017 suggests some senior judges now expect the use of TAR and do not believe any court approval is needed before it is used, see our article.