No, we are not always obligated to obey the law. In cases where harm may come to us if we do obey, disobedience is allowed. Such as committing acts of violence in self defense. Other laws, ones that do not threaten well being of person, are harder to morally justify breaking them, and there is very little criteria that can be applied to EVERY law and EVERY person' morality. One specific criteria, or list of criteria, is far too specific for vast differences in culture, morality, and laws, especially across one country, let alone across the world.
