How to get it Wrong

Lon Fuller, a late great professor of law, describes how to fail to produce good laws.

Lon Fuller, Morality of Law, 2nd rev. edn., (New Haven, Conn.: Yale University Press, 1969)

  The attempt to create and maintain a system of legal rules may miscarry in at least eight ways; there are in this enterprise, if you will, eight distinct routes to disaster. The first and most obvious lies in a failure to achieve rules at all, so that every issue must be decided on an ad hoc basis. The other routes are (2) a failure to publicize, or at least make available to the affected party, the rules he is expected to observe; (3) the abuse of retroactive legislation, which not only cannot itself guide action, but undercuts the integrity of rules prospective in effect, since it puts them under threat of retrospective change; (4) a failure to make rules understandable; (5) the enactment of contradictory rules or (6) rules that require conduct beyond the powers of the affected party; (7) introducing such frequent changes in the rules that the subject cannot orient his action by them; and, finally, (8) a failure of congruence between the rules as announced and their actual administration.  

A total failure in any one of these eight directions does not simply result in a bad system of law; it results in something that is not properly called a legal system at all, except in the Pickwickian sense in which a void contract can still be said to be one kind of contract. 

Fuller called these the “eight demands of the inner morality of law.”