I wrote "last night" that I was going to post something from the livejournal philosophy forum about responsibility and punishment in the absence of free will. It turns out that it wasn't just one comment I was looking for, but several that I wrote in the course of a dialogue. I'll post the meat of them all here, since they pretty much hang together by themselves:
Whether we are deterministic systems or not, we are social creatures with normative attitudes and personal and social commitments, and we cannot live without deciding what to do about each other ("deciding" does not have to mean "choosing" in a metaphysically free sense). We decide what kind of behavior is out of bounds, and those who fulfill their obligations without transgressing the boundaries are said to act ethically. We hold one another responsible for what we do, not because we do it freely, but because our actions originate with us and, once again, we have to decide what to do about each other. As much as there is to discuss here, free will is not a deciding factor in any of these issues.
If not by metaphysically free choice, people's behavior is still determined by complex internal processes that are opaque and unpredictable to others, so people will at least appear to act somewhat freely.
There's no argument from ignorance here; agents act. Their actions proceed from them, and in that sense they are responsible for them. Whether a crime was a praiseworthy or blameworthy act, the person who did it is guilty of that crime and we will decide how to deal with that. We hope that people will feel shame for acting in ways that harm society, and pride for upholding its integrity, and so responsibility matters to us. Observation tells us that people can be expected to behave in the future in much the same way that they have in the past, and also that they are capable of changing with effort and support, and so we can try to alter the person's circumstances and personal history in a way that prevents them from committing that crime again, or helps them to avoid it. By all means, explain at what point free will must enter this process.
The notion of desert is revisable in this way: people should be rewarded, not on the basis of what they have freely earned, but rather on the basis of the kind of behavior that we hope to promote. This means that people will suffer at times for what they could not ultimately avoid doing, and that is tragic. We are tragic creatures living in a tragic world, and this fact should be always before us when we take it upon ourselves to chastise one another.
They're agents if they don't have free will as long as we don't define agency by free will, and I don't. I suppose that, for me, agency is a matter of degree and convention, as both I and a rock are (ultimately non-free) systems capable of causing events to occur, but a rock is not an agent, and I am. An agent is a system that is trusted to act independently and is respected in its autonomy, but also held responsible, as part of its being regarded as a person. We could treat rocks that way, but I think there are good reasons not to.
You might argue that persons must have free will, but you can probably guess what my response would be.