Expensive E-Discovery (EDD) for an Enterprise
IT network backup can store many e-mails that are relevant and discoverable in a lawsuit. But to search for e-mail by way of network backup is very inefficient.
Sometimes, courts do order organizations to go into backup to retrieve computer records - to the vexation of the IT department. The risk that such an order might someday come is one reason for an enterprise to keep plentiful e-mail archives in a system specifically designed for storage and search of large volumes of records.
This risk applies to lawsuits both in the US and elsewhere. A case in point is the Australian decision BT (Australasia) v State of New South Wales & Telstra,  FCA 363 (9 April 1998).
In a commercial dispute between telecommunications carriers, the plaintiff demanded e-mail records from defendant Telstra. Telstra’s records of many of these e-mails were available only in network backup. The court ordered Telstra to search backup tapes, at considerable expense, to retrieve certain e-mails.
Telstra did not have to design its e-mail system so that backup was the archive. Had the company, as a matter of routine policy, treated its e-mails as durable assets of the company – preserved in an archival appliance that allows for easy records search and management – it would not have been forced to rummage through backup for e-discovery.