When we speak of the laws of nature determining or dictating a course of our action, it seems we thereby already assume the determinist conclusion that we have no choice about the nomological constraints. When we say that S is bound to do F by some nomological constraint C, what we are saying is that we expect S to do F under C, just as any other S1, S2, …, Sn which, under C, are shown to do F. In other words, speaking of nomological constraints implies that we expect no surprise or exception under C. Now our expectation can turn out wrong, and therefore the determinist expectation may turn out wrong, too. But the way determinism invokes nomological constraints precludes the possibility that it can be ever disproved: if there were any surprise that violates their deterministic expectation regarding human agency, then they would not consider the expectation nomological at all.
Taking advantage of the fancy Greek term, I may rephrase my point as follows: we ourselves are autonomous, so why should we expect our autonomy to be immediately subsumed and explained away by the supposed law (nómos) of nature? If we are made of stardust and thus part of nature, then our choices and actions can make certain expectations about nature to be true or false. Indeed, it would seem miraculous if our actions turn out to defy the currently established scientific (nomological and deductive) theory of nature. But miracle refers to what we cannot easily understand given our current understanding, not what is impossible to happen. It remains open whether the determinist expectation actually holds true, and invoking the term “law” does not seem to help strengthen the determinist argument.