Iures mores non est

I've been thinking a lot lately about ethics (no surprise, especially because in a month I'll be in classes for my MTS in Christian Ethics (Not counting down or anything).
What has struck me as fascinating is A) the prevalence of Emotivism expressed by even a lot of people I know, and B) the all-to frequent confusion between jurisprudence and ethics.
To let me clear up, first of all, something being legal does not make it ethical, conversely, even if something is ethical, it is not always legal.
To be sure, laws are supposed to be based on ethics. It matters little what sort of ethics (Buddhist, Christian, Judaic, Islamic, Judaeo-Islamic-Christian ethics or what-have-you). All that is clear is that laws are based on ethics (hence, why certain countries have laws that parallel predominant religions' guidelines as well as differences in these countries correlating to this). Thus, we see laws related strongly to religious faith and ethical theories.
However, often times laws stray away from their ethical origins. Such situations include traffic laws, which, though they have life-protecting influences, are not based off of any acknowledge ethical code (some, such as yielding and stopping laws may, but speed limits are often arbitrary).
On a similar note, what is ethical is often illegal. For example, in the nineteenth century in the United States, slavery was legal, and rescuing people from slavery was illegal.
So the fact remains that there are many laws which don't reflect any ethical principle, as there are many ethical principles which don't factor into the law-making process. So, even though the legal system is predominantly based on ethics, it does not submit completely to ethical scrutiny. Similarly, ethical principles often escape or are ignored utterly in the legal process.
St Augustine taught that any law which does not follow truth and ethics is no true law. Thus, a so-called law, whether civil or religious, if it does not stand up to ethical criticism, is not a law that can be enforced, in good conscience.
Nietzsche, as well, in "Genealogy of Morals" (though, admittedly a controversial work) pointed out that what he saw as bad ethics, had affected the development of laws and were thus, (in his view of ethics) a result of bad ethical practices and ignored true ethics.
One might wonder how something like this comes about. The most obvious answer is that people who function as law-makers are motivated by the same things as regular people: money, power, love, salvation, etc. However, the ability to gain more power is easier in a ruling position, and, as the saying goes, "power corrupts." Thus, oftener than not, rulers and law-makers often cater to interests specific to themselves, which go against common ethical sense.
Because of this fact, Thomas Hobbes wrote that in situations in which the people's best interests are not being served, the people are obligated to remove the government. While I am not advocating any drastic measures, what I do mean is that one must not confuse ethics with laws. Often times what's ethical may not be legal, or vice versa. However, you have an ethical duty to follow the ethical over the legal, every time.