One of the great logic errors in ethical discussions is committed by people who shrug off a moral question by saying, “If it is not illegal, then it must be okay to do.” We see a lot of this thinking even among supposedly-conservative defenders of the current leadership in America.
The corollary to that error tends to come from religious fundamentalists, saying, “If it is immoral, it ought to be illegal.” Both of these statements get wrong an important relationship between legality and morality that is best seen by the simple Venn diagram below.
Don’t see these circles as so much depicting “legal versus illegal,” or “moral versus immoral.” Rather consider them as ethical dilemmas where either the language of legality, or instead the language of morality, is most appropriate as the language of discussion. The overlapping shaded slice represents those less common cases where both are appropriate, and often necessary, languages.
Legality and morality are two separate, but overlapping, languages through which our brains interpret ethical challenges, and the languages evolved separately over the last two thousand years. Most of the legal codes in the world’s civilized countries, including the United States (and contrary to those who think our laws have an overtly “Christian” basis) have little to do with morality. Rather they are the rules, indeed they form the language, for social expediency and applied political philosophy, usually without any supernatural assumption attached to theological language. You don’t need “God language” to convict a person of murder.
Most traffic laws, for instance speed limits, are almost always enforced without casting a moral judgment on the driver, and they fall conceptually in the middle of the blue “legality” circle above. The worst case outcome for the offender is usually a fine, and a perhaps some “points” which could accumulate to higher penalties in the future. However, if the speeding gets extreme, and elevated to “reckless driving,” then you can envision the offense moving rightward in the circle toward the shaded overlapping region, where we also start to use the language of morality. At that point, your community likely judges that you have “stepped over the line” to put others in harm’s way, which usually rises to moral offense as well as a more severe legal one.
Similarly, you can usually lie to other people all you want without legal consequence if you can live with the language and consequences of moral disapproval, at some point conceptually inside the red circle above. But if you start lying about money, you are now drifting leftward toward the shaded overlapping slice, and the legal language of fraud comes into the picture. In other words, the law of the United States just does not care about whether you lie in most of life’s circumstances. It is typically only when you lie in the context of other things already illegal that the lie itself becomes illegal.
Note that lying to law enforcement authorities in the U.S. can be a separate crime, but only in the authorities’ pursuit of an active investigation. This is more social expediency than morality. If the lie itself were not an enforceable offense, then the ability of the state to investigate injustice would be severely impeded, if not impossible.
In short, if your proposed action is not illegal, it could still well fall into the sphere of moral disapproval from your peers or religious community. It is just that they usually have no recourse in law to protest your action.
Sex is the second example where, most of the time, your sexual life is not subject to legal review in most modern countries, especially as the last LGBTQ restrictions have fallen for private behavior between consenting adults. It is a moral case for your community of choice, but you typically won’t get prosecuted for your sexual infidelity. When lack of consent by one party comes into the picture, however, so does the language of legality.
There remain, however, extreme moralists who want their religious doctrine enshrined in legal codes, mashing the two circles unnecessarily together into one. This is comparable, at least in intent, to the Islamic extremists who try to turn their particular religious law into harsh legal prohibitions. And there we have the debate. Which “morality” questions ought to have the force of law, and which are best left up to the religious organizations, families or peers to deal with?
In yet another application of this distinction between legality and morality, we have the examples of Gandhi and Martin Luther King, Jr., who often found that exercising their perceived high moral duty specifically required actions that the civil society deemed illegal. This is where the moral conversation gets interesting. But we are usually not there yet.