Voting on emails?
What does it sound like when a commission is reinventing a wheel? Much like this. Guys, the technology you are looking for is called (*gasp*) a forum, with moderators and poster carma and such ...
It would not be too hard to implement a gateway that would receive emails posted to any list and republish then in a web forum where then moderation and voting can take place. Email is unsuited for this because it is impossible to moderate and vote after the message has been sent out (and delaying emails for moderation/voting is a huge burden on communication).