The open records laws apply per the statute to all forms of records, including electronic messages. NDCC 44-04-18.
Access to electronically stored records is free if the records are recoverable without the use of a computer backup. If a request is made for access to a record on a backup or for a copy of an electronically stored record, the public entity may charge a reasonable fee for providing the copies, including costs attributable to the use of information technology resources. NDCC 44-04-18. Electronic records are legally treated the same way as other records in terms of retention and back-up.