BP group email just for admins?

Hi, is it possible (or do you plan to add) to permit just admins (global admin and/or group admin) to send emails to the group members?
Having any member to send a mail to all others its kinda bad... one can join a group and send tons of spam...and you/we surely don't want that, don't you?
It would be better to choose if only the global admin or group admins too