A rule is a tool for the diffusion of conflict. It is an impersonal external reference point, which eliminates the emotional dimension of a dispute between individuals. This impersonalisation of a dispute assists in the creation of order and stability. It does not ensure the creation of the same but merely prods the social organism in that direction.

A retrospective law does not appear fair or just because it fails to some degree to provide an impersonal external reference point. A nagging suspicion that the rule has specifically targeted an individual or group of individuals for the behaviour introduces a personal dimension to the rule.   A law that specifies a conduct to be adhered to prospectively provides participants in a legal system the opportunity to modulate the behaviour.  A conduct ‘x’ that some of us would have engaged in prior to the enactment of the rule could now be abandoned after its enactment.  If the rule was enacted with retrospective effect, it would target and criminalise the conduct of specific persons.  In the United Kingdom, the War Crimes Act of 1991 was specifically targeted at Nazi collaborators.  It did not criminalise a conduct giving good time for individuals to modulate their behaviour to be in accordance with the law.  It criminalised a conduct that had already been committed by specific individuals.  The rule in this instance fails to impersonal.  The important psychological function played by the rule is negated as a result of this.

The personalisation of a rule occurs when the rule is intended to target or perceived to target an individual or a group. The rule then does not operate as an objective norm and acquires the character of a subjective, agenda-laden prescription directed at an individual (with the accompanying lack of the minimal moral legitimacy that objectivity confers).  A rule that is enacted in a vague manner allowing full discretion to the person in authority the power to determine when an offence might be committed is possibly another instance of a rule getting personal.  A statute that states that it is an offence to publish ‘objectionable content’ in a blog leaving the definition of what constitutes ‘objectionable content’ undefined and to be determined on a case by case basis by a state institution acquires the quality of personalisation.  Where the state institution considers party A to be persona non grata, it may utilise this discretionary phrase to arbitrarily deem that party a criminal and where it considers party B to be one that the state considers favourably, it may use the discretion laden in the phrase to acquit the party of any offence.

This personalisation renders the rule questionable. If rules were, to begin with, intended to diffuse conflict and secure tranquillity, any rule that personalises the conflict may be questionable.

These are just some tentative thoughts about some basic principles of the rule of law and as to whether these principles may be analysed from a standpoint of human motivation.  Why do we articulate certain principles of the rule of law as minimum requirements for a legal system?  Is it possible to ascribe a minimum moral commitment to the principles of the rule of law from the perspective that human beings see rules themselves as an impersonal and objective tool to securing order?