loading please wait..

The 5 Ws (and 1 H) of ESI Custodian Interviews

Image of Question Mark


One of the first tasks attorneys must tackle in electronic discovery is assessing the nature and extent of their client’s electronically stored information (ESI). To do that, lawyers must identify ESI custodians and find out what information and knowledge the custodians possess regarding a legal matter. This is often accomplished through custodian interviews or questionnaires.

At the heart of ESI custodian questionnaires and interviews is really just the 5 Ws (and 1 H). The who, what, when where, why and how. Identifying custodians and learning what they know helps satisfy preservation obligations and also helps attorneys effectively represent their clients.



This is really a two part question. First, lawyers must identify the likely ESI custodians, their roles, and who should be interviewed or respond to an ESI questionnaire. They are most often the key witnesses to a case, but also can be departmental representatives and IT personnel.

There is also a second “who” question: Who else? The custodians should also be asked who else possesses electronically stored information and documents related to the legal matter and who else has knowledge about it.



This question is pretty obvious. What does the custodian know about the legal matter and what documents and ESI do they possess?



The duty to preserve relevant information is triggered when litigation is “reasonably anticipated” and identification of data custodians is one of the first steps that must be taken to preserve evidence. If it is unknown who possesses evidence relevant to a legal dispute, it is difficult to preserve it.

In general, it is better to interview custodians earlier in a legal dispute than later. This is especially true if the matter ripened into litigation. It is best to have a workable understanding of your client’s ESI (and the custodians) before engaging in discovery conferences with opposing counsel such as those required under Fed. R. Civ. P. 26(f).

There is also a “when” question that should be directed to the ESI custodians. Specifically, what is the relevant time frame for the legal dispute? Knowing relevant date ranges helps control e-discovery costs and promotes efficiency because data collected, processed and reviewed may limited to time periods in which relevant information is likely to exist. This prevents against over-preservation, over-collection and unnecessary review of irrelevant documents.



One of the most important questions to ask ESI custodians is where they keep relevant information and documents. What electronic devices do they use? Laptops? Desktops? Smartphones? Do they use personal accounts or devices for work related activities? Do they use cloud storage or is the information stored locally or on a server?



The why is not necessarily a question directed to the custodians, but really a question about why it is important to conduct custodian interviews. As noted, utilizing custodian interviews and questionnaires helps satisfy obligations to preserve evidence, but they are also helpful tools to disseminate information about the legal matter, such as litigation holds, and also to document those communications.


(and How?)

The how questions address the custodians’ practices and habits. How do they save and store information? Do they delete items regularly or on a schedule. Do they archive or back-up information, and if so, how? Do they use removable storage devices?


Custodian Interview and Questionnaire Automation

Conducting ESI custodian interviews and using ESI questionnaires are not only e-discovery best practices, but also provide invaluable insight that helps win cases. However the process need not be complicated and time consuming. To conserve our clients’ time and resources, Percipient offers a free automated ESI questionnaire which may be accessed at https://esiquestionnaire.com. To learn more about it, please watch the video on the right sidebar (below on mobile devices), or visit the FAQ page.

Posted on May 19, 2015 in E-Discovery, Electronically Stored Information (ESI), ESI preservation, Evidence

About the Author

Chad Main is an attorney and the founder of Percipient. Prior to founding Percipient, Chad worked as a litigator in Los Angeles and Chicago. He is a member of the Seventh Circuit Electronic Discovery Pilot Program Committee and may be reached at cmain@percipient.co.