Abstract: A method for permitting the secure transmission of electronic messages by using biometric certification is provided. Enrolled fingerprint feature sets, which have been uniquely modified for a particular person with whom messages will be exchanged, are cross-enrolled between the sender and receiver such that the biometric identity of both the sender and receiver can be checked during message sending and receiving. In one embodiment, the sender provides a live-scan fingerprint feature set which is subtracted from the enrolled fingerprint feature set of the sender to create a “difference key” or “difference key” that is used to encrypt the message and other fingerprint data. The receiver decrypts the sender's live-scan fingerprint feature set that is then used to reconstruct the difference key, which is then used to decrypt the message.