Well, there are certainly situations in which you may be required to post (part) of the message, or quote from it. Use your discretion. If it doesn't spoil anything for the rest and isn't directly related to any of the other players, it's probably cool. For instance: an order to search the room of a crewmate should not leave your inbox, while general instructions can be posted. And don't worry, you won't find me on your doorstep with an axe if I don't agree with the choices you make. Well, unless you're willing to tell me where you live.
Calaethis: Yes, since I suspect the number of posts (or PM's) relating to this mission will be limited, anything that happens after you leave Comm-Range is discussed through PM.