According to the natural law tradition, one of the conditions of a true law is that it be promulgated or made known.  There is no such thing as a secret law.  However, there are many ways in which a so-called law may fall short of being authentically promulgated.  The most obvious way is that the so-called law is literally secret.  Public authorities may refuse to divulge to the public the rules and regulations by which they will be judged.

Consider the ordinances against revealing state secrets in the People's Republic of China.  Astonishingly, many of the rules and regulations about state secrets are themselves secret, so there is no way to know whether or not one is in violation.  Trials held under the law are also held in secret.  Among those punished have been Shi Tao, a newspaper reporter, sentenced in 2005 to ten years in prison for "illegally supplying state secrets abroad";' Tohti Tunyaz, a University of Tokyo doctoral student studying Chinese ethnic minority policy, sentenced in 1998 to eleven years in prison for "illegally procuring state secrets"; and Rebiya Kadeer, an advocate for the Muslim Uighur minority, sentenced in 1999 to eight years for "illegally providing state secrets overseas."  What were their crimes -- what did they actually do?  Tao had posted online a summary of official restrictions on Chinese press coverage of events related to the fifteenth anniversary of the Tienanmin Square massacre.  Tunyaz had retrieved fifty-year-old records from a library.  Kadeer had mailed Chinese newspaper clippings to her husband in the United States.

But the expression "secret law" should also be extended to laws that are not literally secret, but secret in effect.  Consider vague enactments, rules that are cast in language so elastic that no one is sure of its meaning, or the meaning of which is unpredictably extended through excessively supple rules of interpretation.  During the past century this sort of elasticity has been a prominent feature of all of the totalitarian legal codes.  As Alexandr Solzhenitsyn wrote of the infamous Article 58, “Wherever the law is, crime can be found.”

The glories of elasticity are often trumpeted even in the liberal democracies that fancy themselves avatars of rule of law.  In the United States, they are sung in paeans to the so-called "living" constitution, and in the abominable theory that "law is whatever judges say it is."  But liberal democracies have invented a new failure of promulgation, a novel kind of "secret law" for which credit is theirs alone.  For promulgation can fail -- the rules can be unknown -- not only when they are literally secret, retroactively applied, excessively vague, or arbitrarily interpreted, but even when there are simply too complex.  To put it another way, the very impulse to turn everything into law can be prejudicial to law, for then the rules become so vast, multiform, and changeable that no one can learn them, much less grasp what they mean.

In 2010, investigators for the U.S. Treasury Department, pretending to be taxpayers, found that Internal Revenue Service Centers set up for taxpayer assistance gave either no answers, incomplete answers, or incorrect answers to their questions 43 percent of the time.  The root of the problem is not simply that taxpayer assistance workers are insufficiently trained, but that the tax code has become too complex for anyone to learn as a whole. 

The community has entrusted the power of making laws to Congress, but Congress long ago gave up the principle delegata potestas non potest delegari, "the one to whom a power is delegated may not delegate it to another."  Congressional enactments alone run to three or four thousand pages, but if we add in the regulations drawn up by the administrative agencies, the tax code comes to 20 volumes.  Bear in mind that taxation is only one of the fifty subject headings in the Code of Federal Regulations, now tens of thousands of pages in length.

As early as 1788, James Madison had foreseen such a possibility.  Mutability of the laws is "calamitous," he warned.  "It poisons the blessing of liberty itself," for “It will be of little avail to the people, that the laws are made by men of their own choice, if the laws be so voluminous that they cannot be read, or so incoherent that they cannot be understood; if they be repealed or revised before they are promulgated, or undergo such incessant changes that no man, who knows what the law is to-day, can guess what it will be to-morrow.  Law is defined to be a rule of action; but how can that be a rule, which is little known, and less fixed?”

The rule of law, it seems, is not the same as the rule of a multitude of regulations, and there is a difference between publishing the rules and promulgating them.  If the law is so copious and profuse that the people cannot take it in, so intricate and involved that they cannot understand it, or so mutable and mercurial that they cannot keep track of it, then it has not been truly promulgated; and so it is not truly law.  What does this fact suggest about the legitimacy of the modern administrative state?

Commentary on Thomas Aquinas’s Treatise on Law