As part of my ongoing discussion about ESI collection issues, I want to spend more time on the custodial interview process, because the interview is a critical part of any defensible collection. First, you must identify custodians, their locations and the data storage devices they use, not just for e-mail, but for other data as well.  Be sure to also identify custodians who may have left the organization but were there during the relevant time period.

So, how do you go about interviewing custodians once identified?  The important point to remember is to ask very detailed questions to custodians about locations of data.  The best place to start is to find out if the client has a data map — information (graphic or text based) that shows every source of data within a company.  It can make life much easier if the client has this.

You should question custodians about possible local storage sources, such as laptops, personal computers, USB drives, digital media (CDs, DVDs), and smartphones.  You should also question custodians about cloud storage, virtual networks, dropbox or things of that sort.  Keep in mind that many people do not even know they are participating in cloud storage.  For example, if you have an iPhone, you can unknowingly be part of the iCloud. The iPhone provides "yes" as the default, and it is not unusual for an iPhone user to overlook this.  Be sure to ask custodians to doublecheck.  In addition, you want to look to serverlevel storage, such as networked drives, share points, databases, internet pages, lotus notes and group wise.

E‑mail storage opens a whole other can of worms.  Be sure to check for local mailbox storage.  This is where e‑mails reside locally on the client's laptop or desktop.  In addition, for those who use Outlook, look for .pst files.  Outlook creates these by default, but the user can export certain categories of e‑mails to single or multiple .pstfiles that can be stored locally, in the cloud or at the server level.

For each custodian interviewed, you must ask very detailed questions about how they manage their e‑mail. For example, are the e‑mails exported to devices such as thumb drives?  Are they sent to personal e‑mail accounts such as Yahoo or Gmail accounts? Do they maintain paper files and important e‑mails?  Is the custodian a data base custodian? Do they use smart phones for work e‑mails?  Do they use their home computer for work e‑mails?

Don't overlook non-custodian specific data.  At the company (non‑custodian level), someone, like the chief technology officer or chief information officer, should identify all databases and other source of data that are maintained that are non‑custodian specific.

And of course, don't forget paper files (yes, they still exist!).  These are frequently overlooked in the ESI collection process, but are necessarily part of the mix, particularly for cases and/or issues that go back many years.

I plan to write further about ESI issues in coming months.  Stand by.

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