Gloves, I couldn't help but notice you kinda took what Rennac said out of context. the violent bit came up after Hay asked what would happen if it wasn't safe and that the group in the colony were in fact looking to kill them. 

Hay: "I know, we need to know, but still. What if it isn't save? What then?"
Rennac: "Stab first, shoot second, slit a throat here and there, and ask the last survivor what they were doing there with a knife against their throat. Surprising how talkative someone can get with a knife at their windpipe."

He never said he was going to do that to a civilian.