Robert's Rules of Order (10th edition page 414) A "proxy" is a power of attorney given by one person to another to vote in his stead;... It goes on to note that it is not permitted unless in the bylaws. (and remember to change that provision you are looking at a few meetings)
"Absentee" voting on the other hand (page 408) talks about limiting the right to vote to members of an organization who are actually present at the time a vote is taken. Exceptions to this rule must be expressly stated in the bylaws. The only exceptions to the rule would be postal, electronic mail or fax voting and must be in the bylaws.
Reasoning behind these is the principal of parliamentary law that the right to vote is limited to the members of an organziaiton who are actually present at the time of vote in a legal meeting.
If Robert's Rules is not the parliamentary authority of your association I do not know how to advise.
It is tough at board meetings because you cannot bring anyone else in to assure the vote. Hope this helps.
