A favorite refrain on the right as a part of the immigration debate is: 'What part of illegal don't you understand?'
As a rhetorical question, it gets at the issue of language, but uses the law as its primary ethical appeal. The unvoiced assumption in the syllogism is that we all conduct ourselves in a manner in accordance with the "law."
In Chapter 10 of Book I in Rhetoric, Aristotle makes the point that there are two kinds of law: the specific to a community, and the understanding that exists within the social contract of treating one another civil.
“We may describe "wrong-doing" as injury voluntarily inflicted contrary to law. "Law" is either special or general. By special law I mean that written law which regulates the life of a particular community; by general law, all those unwritten principles which are supposed to be acknowledged everywhere” (Book I, Chapter 10 1369a)
While the "law" is often deployed as an end all to public discussions about right and wrong, the presupposed acknowledged understanding between humans goes ignored, and unacknowledged.