How can we look at a legal system? H.L.A. Hart famously deployed the distinction between external and internal perspectives on a legal system in his famous book, The Concept of Law. This post provides a very brief introduction to this distinction for law students (especially first-year law students) with an interest in legal theory.
Internal and External What is the difference between internal and external perspectives on the law? Obviously, we are dealing with a metaphor here. The idea is that one can look at the law from the inside or from the outside. Even if you have never encountered this distinction before, the intuitive idea is fairly clear. The internal point of view is the perspective of participants in the system. Thus, the internal point of view is paradigmatically the point of view of legal officials (such a judges). The external point of view is the perspective of outsiders. Thus, the external point of view is paradigmatically the point of view of a sociologist or anthropologist from a different culture, who observes the legal system.
Here are some examples:
--Doctrinal theories (e.g. a theory of the Commerce Clause of the United States Constitution) are usually stated from the internal point of view. This is the kind of theory that law students usually encounter early in their legal education.
--Causal theories (e.g. a public-choice theory that explains why a particular area of law has come to be the way it is) are usually stated from the external point of view. In first-year law school courses, causal theories are usually stated in a very compact, even off-hand form. There may be a brief classroom discussion of the causal forces that shaped a particular legal doctrine, but it is fairly rare actually to read social science literature on topics like this.
Rules and the Internal Point of View The internal point of view may have additional significance to legal theorists. One can argue that legal rules cannot be described from a purely external point of view. Huh? Imagine that you are an anthropologist from Mars, observing an earthly legal system. You would be able to note various regularities in behavior, but so long as you stuck to the purely external point of view, you would not be able to say anything about the content of the laws. In order to do that, you would need to ask the question "What is the meaning of the these legal texts and actions?" And to say anything about meaning, you would need to assume (at least hypothetically) something like the internal point of view. You would need to ask the question, "What does these behaviors are markings mean to those who are inside the practice of law?"
If this argument is correct, then important consequences follow. Legal theorists are interested in legal theory. If the internal point of view is a necessary prerequisite for understanding the legal significance of the behavior of legal actors, then it would seem to follow that all legal theory requires that the theorist be able to assume the internal point of view at the stage where the theorist describes the legal phenomenon that are the object of study.
Let me give an example of this rather abstract point. Suppose you want to develop a causal theory of tort law. You want to argue that there is an economic explanation of the emergence of negligence (as opposed to strict liability) as the primary standard of care in tort. The details of the theory don't matter, but let's assume you believe that inefficient legal standards create incentives for litigation and that a quasi-evolutionary process leads to the selection of efficient standards. And of course, you would need to argue that negligence is efficient. This theory is primarily stated from the external point of view, but it also relies on the legal meaning of the distinction between "negligence" and "strict liability"--concepts that can only be understood from the legal point of view.
The central idea here is that the external point of view can describe the behavior of legal actors, but the internal point of view is required to understand the meaning of legal actions.
Conclusion The distinction between the internal and external point of views is one of the basic ideas in legal theory. When you first begin to construct theories about the law, you should ask yourself, "Am I looking at this area of the law from the internal point of view or am I taking a perspective that is external to the law?" For more on theory construction, you might also want to look at an earlier post in the Legal Theory Lexicon series: Legal Theory Lexicon 016: Positive and Normative Legal Theories