Battlestar Galactica: Razor

I finally sat down and watched Razor last night. I liked it; although I was not as excited about the old-school Cylons as everyone else seems to be. One thing really struck me as unrealistic.

*Spoiler Alert*

The 3 big Cain's a sadistic killer moments were the execution of her XO, the instructions to torture Gina-6 and the order to execute civilians.

In the real world, I could see the last 2 actually happening. Similar torture has happened and probably is still happening in Iraq. And it would seem even easier given the Cylons wouldn't be viewed as people, rather robots. Given the stress of the Colonial-genocide and the previous potrayal of inter-colony bogotry the execution of civilians is not impossible to imagine under the fear of being executed yourself for insubordination.

But, I can't think of an instance were an XO was executed for refusing to obey an order. I mean, I can see Cain's character doing it. But I would think that well trained colonial officers would have done something like take Cain into custody. Maybe if there was a history of the XO and Cain butting heads; but so early on and in a situation that had not yet spiraled out of control. Maybe I am naive but it didn't strike me as possible. Does anyone know of any similar, real life examples in modern history?