I think that we are attempting here to discuss two different types of morality... one is the morality of laws intended to keep society as a whole safe, ie murder, rape, theft, speeding, etc; the other is the morality of soul or religion if you will, such as incest, homosexuality, coventing what others have but not acting on it, adultery, keeping the Sabbath, obeying one's parents, etc.
One can and certain should be legislated, the morality intended to keep society safe; but the other morality can not be legislated and when a society attempts to do so, there is usually a lot of breaking of those laws, often in private. Take for instance the laws against sodomy or oral sex, many states carried these laws for decades, but were unenforcable. We are seeing such a case in California with the attempt to legislate against gay marriage, even though the "majority" have voted against it, the courts found that this type of "morality" does not fit into the category of one that would harm society.