Dang, here we go again. UCMJ says private conversations are protected from that peculiarity of "disrespect towards superiors and elected officials", right? Therefore, unless someone overhears it, the only way you have to answer for it is if someone in that conversation dimes you out. And the only just cause for that is if you're talking treason, which no one here is.
So if you don't like what someone says, and you don't like it enough, PM the administrators and have the offending entity removed from the members list. Fly/Brett/A4s have set a good example on this before. Threats of revealing someone to the board are unbecoming; when we say it's not private, we mean it can be subpoenaed, not that someone with a grudge will email it to everyone in the RAG. If you've done this, I don't care how junior I am, you're a dick and you need to cut back on the 'net time.
Anyone who strongly disagrees with this suggestion, send me a PM with my name, rank, and organization and I'll STFU.