1. There is a distinction between a law of nature and a law of science. If there are laws of nature, they have nothing to do with us or our theorizing. They are 'out there in the world.' For example, if we adopt a regularity theory of laws, and I am not saying we should, the regularities, and thus the laws, exist independently of our theorizing. Surely, if there are physical laws at all, and whatever their exact nature, their existence antedates ours. Laws of science, on the other hand, are our attempts at formulating and expressing the laws of nature. They are human creations. Since physics is a human activity, there were no laws of physics before human beings came on the scene; but there were physical laws before we came on the scene. Physics is not the same as nature; physics is the study of nature, our study of nature. It is obvious that physics cannot exist without nature, for it would then have no object, but nature can get on quite well without physics.
2. Given the distinction just made, it is quite easy to see how one could come to the view that true scientific laws are not simply true, but true ceteris paribus, 'other things being equal.' Coulomb's Law states that particles of like charge repel and particles of unlike charge attract. But one can think of exceptions. Suppose the gravitational attraction between two particles of like charge is greater than the electrical repulsion. Is this an exception to Coulomb's Law? If it is, it is an exception to a scientific law, not to a physical law. Again, a law of science is different from a law of nature. Science, as the study of nature, is not nature. Therefore, from the fact, if it is a fact, that scientific laws have exceptions, it does not follow that physical laws have exceptions.
3. We should also not confuse laws of nature with natural laws in the ethical sense. The topic, laws of nature, belongs in metaphysics, not ethics. And since laws of nature are not to be confused with their approximation in scientific laws, laws of nature is not a topic of epistemology.
4. Applying these distinctions to our question about the possibility of ontic miracles (not epistemic marvels), I want to say that pointing to ceteris paribus laws has no tendency to show that ontic miracles are possible. For any law that has a ceteris paribus clause is ipso facto a scientific law, not a law of nature. A miracle, however, is a violation or suspension of a law of nature.
Compare Norman Swartz on Physical Laws and Scientific Laws.