The law is as serviceable for evil as it is for good.
Austin's Command Theory states that laws are a command of the sovereign and these commands may be good or evil. They are enforced by the use of brute force upon those who do not adhere to these commands.
Kelsen claims that the validity of law comes from a series of unbroken norms followed by convention. These link back to the grundnorm.
The legal standards are determined by conformity to conventionally accepted criteria of legal validity, on which there are no moral restrictions.
This is superior to Austin's brute force view as Hart explains how the law has a distinctive way of making conduct non-optional by contrast with the use of force.
Beyleveld and Brownsword say that this cannot be the case as officials must consider that their standards are moral. Hart says that the judges must regard the fact that Parliament enacted the provision as reason in itself to obey it, and not moral reasons relating to the law. It should not be read too much into that both law and morality use the terms 'rights and 'duties'.
Legal reasoning is not always factual and judges may refer to moral considerations when making judgments. There are therefore, no boundaries on the judges rule of recognition; it may be moral or it may be factual. The United States measure their laws against the Bill of Rights which means the validity of laws are tested for fairness.
Legal norms are such due to a matter of social convention, and the social mood can be either unjust or moral. This theory is not a threat to the separability thesis; it does not say the link between law and morality is impossible, but it is simply unnecessary.
Dworkin criticises this form of positivism. He says that the identification of law in every system does necessarily involve moral judgements and inclusive positivism is not positivism at all due to the large amounts of inconsistencies between this and other theories. Finally, he says that you cannot accept a controversial moral criteria of legal validity whilst having a factual test for determining the law.
Hart disputes these comments. He says it is necessary to distinguish between disagreement over the content of rules and disagreement over the applicability of the rules.
Dworkin also says that moral tests cannot ensure reliable public standards of conduct as morals are always controversial due to the various different opinions over which conduct is moral or not. Hart says this is not a problem; the law doesn't always need to be certain and flexibility can be useful for ensuring that judgements are correct and appropriate for the case at hand. Furthermore, he says that moral tests are not always controversial and some moral questions have clear and easy answers.
Joseph Raz is the main exponent of exclusive positivism.This theory takes the plain-fact view which was set out by Dworkin and believes that all criteria of legal validity must be source based as moral tests are inconsistent with the nature of law.
Raz distinguishes between first order and second order reasons for doing things. First order reasons are those which make us want to do a particular activity. Second order reasons are those provided by authority which cause us to re-evaluate our first order reasons and may cause us to change our mind about the activity we were going to perform. Authority is therefore justified if we are more likely to comply with reasons that apply to us if we obey authority. This is the service conception of authority, it performs a service in allowing us to comply with our own reasons.
In order to be seen to be legitimate, law must be capable of possessing legitimate authority and this can be in a number of ways. Firstly, the rules must be presented as the law-makers view of how we should behave, so other people believe that it is the correct way to in fact behave, the rules must be established by reference to historical sources.
If the merits of the rule must be examined, it will be unable to function as authority, the authority is meant to replace our rules and not be weighed against them. This point can be disputed. People may ask why our reasons should be replaced altogether, as this suggests we are not capable of choosing ourselves what to do so we need authority to choose on behalf of us. The answer to this is that the morality applied by judges does not become incorporated into the law and the statute allows the judge to go beyond the law when making a decision.