Is it possible to process the messages received by members of a distribution list?

You cannot directly use address lists in rules. However, in MRE it is possible to create rules which have, as a criterion, the presence of the user in an address list. When a message is delivered to a member of the specified address list — all messages arriving to addressees who are members of the specified address list are processed.

It is possible to use dynamic address lists, on the basis of LDAP cubes, to check for the presence of a receiver in security or distribution groups.