(1) legal (and related cutom and practice) requirements for people sending
messages (along the lines of those required in USA for fax transmission:
identity of sender, timestamp, etc.). I think it is appropriate for this
group to consider this to the extent of providing tecxhnical measures that
align with fax practice.
(2) requirements for a transmitted document to have any free-standing
evidential weight. This latter case is much more complex, and has much
less case lore (sic) behind it (though more than none at all). A full
treatment of this would be way beyond the scope of this group. As
technicians, we should probably try to avoid obvious problem areas (e.g. by
allowing for authentication, etc.) but not kid ourselves we can completely
solve a problem that has significant non-tecnical components.