Read this: However, it is important to understand that despite the presence of reception statutes, much of contemporary American common law has diverged significantly from English common law. The reason is that although the courts of the various Commonwealth nations are often influenced by each other's rulings, American courts rarely follow post-Revolution Commonwealth rulings unless there is no American ruling on point, the facts and law at issue are nearly identical, and the reasoning is strongly persuasive.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): When would American courts follow post-revolution commonwealth rulings?
there is no American ruling on point