One of the biggest differences between unethical conduct and criminal
conduct by government officials is the matter of proving intent. For
example, a bribe is nothing more than a gift to a government official
where it has been proven that the official intentionally took a gift in return for certain conduct. In government ethics, taking a gift beyond a certain value is all that needs to be proven to show misconduct. The official's conduct, beyond accepting the gift, is
irrelevant, as is the official's intent.
But what about knowledge? Clearly, if it can be shown that the official
knew nothing about a gift, that an envelope containing $10,000 had been
placed under his porch without his knowledge, it would not be
considered receipt of a gift. But if the gift were given to his wife, and he
insists she never told him about it, it's still an ethics violation.