Not yet, but we plan to have them do so in the future. However, when NPCs or players die a lot, it will reduce NPC happiness for a while, which will in turn reduce their productivity. So even now there are consequences. But Keith and I have talked about doing a lot of much cooler things with NPC reactions to having each other be killed, such as having them turn hostile, or even send out bounty hunters after your character if you've really been on a murder spree with them.
I'm always reluctant to discuss conjectural features like that because some people then think "this is coming, and it's coming soon," when in reality that's not the case. If there's a lot of interest in having the NPCs react more to things like that in beta, then I imagine we'll look at it sooner than later. I personally think that a GTA-style "avoid the bounty hunters and roadblocks of the NPCs that are mad that you're a murderer" sounds like an awesomely fun time (and of course if we did that, we'd need a way to get into that gameplay mode that would not involve murdering innocent people -- some sort of evil bounty hunter event that could be triggered, basically).
But anyway, this is a giant and a complex game engine, and there are a lot of ways that we could take it as we're increasingly getting into content development. We're going to be developing like mad during beta either way, but a lot of what specifically gets implemented depends on what people are showing the most interest in, what we find most fun, what ideas occur to us or get suggested during beta, etc. So it's possible that features like this could get delayed indefinitely or never happen, but that would just be because there were more-cool things that we were focusing on instead.
There's not a technical barrier here, anyhow, is what I'm saying. It's just the time to implement and thus the opportunity cost of whatever other features we would have implemented instead.