Law — what it is, where it comes from, how it changes — is not as simple a concept as many believe it to be. The modern popular myth is that law is created by government, so that in democratic countries, law is created by The People exclusively through their representatives. Statutes and regulations duly enacted by the state are, under this view, “the law.”
This account of the law is grossly incomplete. Much law (I would argue most law ) emerges spontaneously in the course of multitudes of human interactions and is never — or only after the fact — written down in a statute book. In addition, much “law” that is written in statute books truly isn’t law in any operational sense. (Is it really unlawful to jaywalk? Or to drive at 60 mph on a highway whose posted speed limit is 55 mph? )
Greater recognition that promulgation by the state is neither a necessary nor a sufficient condition for a rule to become law would make the current debate over immigration much more fruitful and much less shrill. (So, too, would the recognition that violation of some laws are more serious than are violation of other laws.)
This essay  by Lawrence Downes appearing in Sunday’s New York Times makes an important point. Here are the opening paragraphs:
I am a human pileup of illegality. I am an illegal driver and an illegal parker and even an illegal walker, having at various times stretched or broken various laws and regulations that govern those parts of life. The offenses were trivial, and I feel sure I could endure the punishments — penalties and fines — and get on with my life. Nobody would deny me the chance to rehabilitate myself. Look at Martha Stewart, illegal stock trader, and George Steinbrenner, illegal campaign donor, to name two illegals whose crimes exceeded mine.
Good thing I am not an illegal immigrant. There is no way out of that trap. It’s the crime you can’t make amends for. Nothing short of deportation will free you from it, such is the mood of the country today. And that is a problem.
America has a big problem with illegal immigration, but a big part of it stems from the word “illegal.” It pollutes the debate. It blocks solutions. Used dispassionately and technically, there is nothing wrong with it. Used as an irreducible modifier for a large and largely decent group of people, it is badly damaging. And as a code word for racial and ethnic hatred, it is detestable.