There are a few exceptions to the general prohibition against filing a second writ. One of those exceptions is, “new evidence
” that could not have been found through due diligence, either at the time of trial or at the time the second writ of habeas corpus
was filed. A second exception is that if the United States Supreme Court has issued an opinion that changes the law dramatically, such as that could not have been reasonably anticipated, then the question becomes whether or not the new law will be applied retroactively or not. The rules regarding retroactivity are complex, but this is one of the second exceptions. There are other legal exceptions.