The "problem" of free will escapes me. Some seem to think that free will means that human decisions are not deterministic, i.e., that they are unpredictable. That makes no sense to me. The fact that you can predict, in advance, that I will make a certain choice does not change the fact that the choice is mine to make. I will always choose tuna sushi over natto. I could, if I wanted, chose differently. But it happens that I like tuna, and not natto, so I always choose the former. Still, it is my choice. I could choose otherwise, if I wanted to, but I don't.
Being undeterministic is not the same as having free will. Quantum mechanics tells us that an electron behaves unpredictably, but an electron does not therefore have free will. Or at least there is no reason to believe that it does. Indeed, although the behavior of a particular electron is not strictly predictable, the behavior of a large group of electrons is. That is because quantum mechanics tells us the odds that an electron will take a certain path. The choice of each electron is not really "unpredictable" at all. If being undeterministic is "free will," then there really is not such thing.
The false "problem" of free will seems to be a function of a misunderstanding of the term "I." The fact that you can, theoretically at least, always predict in advance what I am going to chose does not change the fact that I made the choice. Now, if I am served natto, no matter what I request, then of course I did not have a choice in the matter.
This brings me to the issue of accountability and blame. Perhaps I am destinted to commit a terrible crime. It is a certainty that I will chose to kill a man. Can I be blamed? After all, I am exactly what my genetic background and my upbringing, and given those facts about my existence, it is certain what I will do. Circumstances may have conspired to make me a bad person, someone who chooses to do evil things. Still, that does not chance the fact that I can still be blamed for what I do, so long as I have a choice.
By "choice" I mean that circumstances are such that, if another person were in the same circumstances as I, the result might be different. For example, if I am driving and decide to run a red light, you (and many other people) would have been able to act differently. You would have stepped on the brake. Assuming that the brakes work, my running the red light was a choice.
Of course, there are all sorts of problematic cases, such as where my leg spasms, and I am not able to step on the brake. Most people would not blame me under those circumstances, yet you would have done better had you been in my place. It seems that, in this example, my body and not my brain made the "choice." Without getting into a mind-body argument, this seems like a clear example of a decision made by my body, for which I am not morally responsible. Strictly speaking, however, perhaps I did have a "choice," as I have defined it. Of course, change the example to add the fact that I was taking medication that I knew gave me leg spasms, and perhaps I am to blame again.
And what about people who do things under the influence of drugs or mental illness? At least by my definition, they have still chosen to do whatever it is that they do. Perhaps the moral implications are different, depending on the complete circumstances, but the drunk person still chooses to punch someone in the nose.