In the Navy, two commanding officers (a CO and an XO) were fired for fraternization. Both officers were Lt. Commanders working on the same ship. http://www.navytimes.com/news/2010/12/navy-mcm-chief-co-xo-fired-120910w/ During the discussion, the CO indicated he didn't have a sexual relationship with the XO. And in the discussion, it seems things like including invitations to one because you're more friendly with that person could be considered fraternization. I think that brings back an age old question with a new lens. What would've really happened with Archer/T'Pol and/or T'Pol/Trip (whichever you believe you'd like to answer for in whichever respect).