Getting Smart With Email In E-Discovery – How Email Threading Can Lower Costs And Increase Speed: A Case Study With Perkins Coie And Discovia

Tuesday, March 25, 2014 - 13:10
The Email Challenge

Email volume is exploding. Email is still the predominant form of business communication, with over 100 billion business email messages sent and received each day (Radicati Group). What was once a quick call to Sandra down the hall is now a long email chain, leaving a multi-message trail that may need to be processed and reviewed during litigation. This massive volume of email can easily result in wasted time and effort during e-discovery document reviews. Message-by-message reviews, rooted in the days of paper, are inefficient and can lead to inconsistent coding decisions.

Email threading is a more contemporary approach that can help organizations save time and money in e-discovery. Email threading technology reconstructs email threads, enabling the presentation of messages within the entire thread or family from which the email originated. Email threading offers litigation teams a simplified way to review email during the document review process. In addition, email threading addresses the reality that the full meaning of many messages might only be clear when they are viewed in context.

Email threading can also reduce inconsistent coding decisions made during document review – something that not only wastes money, but can also prove risky if it results in a failure to produce responsive documents. In addition, email threading can help litigation teams sharpen their focus on the data they need to build their case, enabling smarter case strategy.

Email Threading​ In Practice

E-discovery success depends upon strong partnerships. Perkins Coie has teamed up with Discovia, a managed e-discovery services provider, to incorporate email threading technology from Equivio into their document review process. The rapid growth of email as a target in litigation demands innovation. Even a “small” case for Perkins Coie can involve 70 gigabytes of email or more.

Their litigation team uses the technology to identify, group together, and reconstruct the chain of email conversations (i.e., the email “thread”). The technology also analyzes email content to identify the most comprehensive and unique content in the email thread. Combined, these techniques increase review throughput and thus reduce costs significantly.

Perkins Coie’s Practice Technology Services Project Management (“PTS PM”) team, led by Janelle Eveland Belling, has developed three email threading models that they are able to employ on a case-by-case basis. When one of these models is employed, review is conducted in the context of the reconstructed email thread and messages are reviewed together with their attachments. The models differ only in the extent to which redundant email messages are “suppressed,” and thus not seen by document reviewers. The three models are described below.

  1. No email suppression. All messages, together with their attachments, are reviewed as part of their original thread.
  2. Conservative email suppression. Before document review commences, duplicate messages are suppressed. Unique messages are flagged for review, including those that contain unique attachments. Messages that do not contain any unique content and do not contain a unique attachment are not reviewed.
  3. Aggressive email suppression. Only the longest unique messages and any unique attachments are reviewed.

The firm uses the second model (conservative email suppression) most often. However, they see increasing acceptance of more aggressive strategies, which can significantly reduce review volumes, as discussed below. 

Education Aids Adoption

As e-discovery has evolved, technology like email threading has become essential, but it can be difficult to explain to people who are not immersed in the rapidly changing e-discovery world. Perkins Coie has found that visuals are the easiest way to help people understand the technology and its application. As such, it has created a slide deck with many graphics that represent the different models. This presentation helps greatly in both internal and external discussions about the models. The Perkins Coie PTS PM team has also focused on developing and implementing tight quality controls that have helped with acceptance by their own attorneys and by opposing counsel.

Email Threading Results And Benefits

Increasing Speed

Email threading increases review speed. Based on Perkins Coie experience, the average acceleration of document review speed is approximately 15-20 percent. This means, for example, that the firm’s reviewers can review ten or more documents per hour once they are introduced to threading.

Reducing Volumes

Equivio’s email threading technology can significantly reduce the number of documents requiring review. For example, in the following cases, Perkins Coie was able to reduce the number of documents reviewed (and thus the cost) by 18-45 percent.

  • In a case with over 460,000 documents, using the conservative model, Perkins Coie was able to suppress approximately 83,000 documents, a reduction of 18 percent.
  • In another matter with over 67,000 documents, using the conservative suppression model, Perkins Coie suppressed over 22,000 documents – a 33 percent reduction.
  • The aggressive model results in even more savings: on a matter with over 137,000 documents, Perkins Coie saw a 37 percent reduction, and in another involving 188,000 documents, the total reduction of email reviewed was 45 percent.

More Consistent Document Production and Review

The firm has also found that email threading improves review consistency. The presentation of email messages in the structure of the original thread allows review tags to be applied consistently either across the entire thread, or unique tags to be applied to different portions of the thread.

The Result: Big Cost Savings

Email threading offers a one-two punch that has created big savings for Perkins Coie. The first punch is increased review speed and consistency. Perkins Coie has found that this reduces review costs 15-20 percent. The second punch is email suppression, which can reduce review volumes up to 45 percent. The total savings from the technology has reduced total email review costs by up to 65 percent. These savings have added up to hundreds of thousands of dollars in large matters, and into the millions in mega-cases.

In Summary

Equivio’s threading technology has enabled Perkins Coie to adapt to the ongoing growth of email evidence and thus continue to provide efficient and effective document review services to its clients. Email threading speeds the review process, lowering costs up to 65 percent. The firm has also found that email threading enhances document review quality by helping reviewers to more consistently tag messages in each branch of the thread. With compelling, quantifiable benefits, Equivio’s email threading technology has become a standard approach for email discovery at the firm. 

Barclay T. Blair is an advisor to Fortune 500 companies, software and hardware vendors, and government institutions, and is an author, speaker, and internationally recognized authority on information governance. He has led several high-profile consulting engagements at the world’s leading institutions to help them globally transform the way they manage information. He is the president and founder of ViaLumina.


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