The virtual legal reasoning box we are imagining will clearly need to either contain the data it needs, or be able to reach outside of the box and access whatever data it needs for its legal analysis. In other words, we can imagine the box having the ability to pro-actively reach out and grab legal data from the outside world when it needs it. And/or we can also imagine the box directly storing data so that it does not need to reach out and get it.
This brings us to the first little conceptual maneuver we are going to make in order to make reasoning about this whole thing a bit easier. Namely, we are going to treat all legal data that ends up inside the box for the legal analysis as having arrived there from somewhere else. In other words, we don't have to split our thinking into stored-versus-retrieved legal data. All data leveraged by the legal reasoning box is, ultimately, retrieved from somewhere else. It may be that for convenience, some of the retrieved data is also stored inside the box but that is really just an optimization - a form of data caching - that we are not going to concern ourselves with at an architectural level as it does not impact the conceptual model.
A nice side effect of this all-data-is-external conceptualization is that it mirrors how the real world of legal decision making in a democracy is supposed to work. That is, the law itself does not have any private data component. The law itself is a corpus of materials available (more on this availability point later!) to all those who must obey the law. Ignorance of the law is no defense.[1]
The law is a body of knowledge that is"out there" and we all, in principle, have access to the laws we must obey. When a human being is working on a legal analysis, they do so by getting the law from "out there" into their brains for consideration. In other words, the human brain acts as a cache for legal materials during the analysis process. If the brain forgets, the material can be refreshed and nothing is lost. If my brain and your brain are both reaching out to find the law at time T, we both - in principle - are looking at exactly the same corpus of knowledge.
I am reminded of John Adams statement that government should be "A government of laws, not of men."[2] i.e. I might have a notion of what is legal and you might have a different notion of what is legal but because the law is "out there" - external to both of us - we can both be satisfied that we are both looking at the same corpus of law which is fully external to both of us. We may well interpret it differently, but that is another matter, we will be returning to later.
I am also reminded of Ronald Dworkin's Law as Integrity[3] which conceptualizes law as a corpus that is shared by and interpreted for, the community that creates it. Again, the word "interpretation" comes up, but that is another days work. One thing at a time...
So what actually lives purely inside the box if the law itself does not? Well, I conceptualize
it as the legal analysis apparatus itself, as opposed to any materials consumed by that apparatus. Why do I think of this as being inside and not outside the box? Primarily because it reflects how the real world of law actually works. A key point, indeed a feature, of the world of law, is that it is not based on one analysis box. It is, in fact lots and lots of boxes. One for each lawyer and each judge and each court in a jurisdiction...
Legal systems are structured so that these analysis boxes can be chained together in an escalation chain (e.g. district courts, appeal courts, supreme courts etc.) The decision issued by one box can be appealed to a higher box in the decision-making hierarchy. Two boxes at the same level in the hierarchy might look at the facts of a case and arrive at diametrically opposing opinions. Two judges in the same court, looking at the same case might also come to diametrically different opinions of the same set of facts presented to the court.
This is the point at which most IT people start to furrow their brows because it goes against the grain of most other computational systems that they work on. The law is not a set of predicate calculus rules that can combined in a classical conditional logic system. There are very few black and white predicate functions in law. This is not a bug. It is a feature. This is not a lack of logic either. Rather, it is a different type of logic, known as non-monotonic logic[4]. Just as valid and just as useful and necessary as the Boolean Logic IT people are more familiar with.
We will be returning to this later on. For now, suffice it to say that the logic of the analysis process is considered to be inside the box because it is private in the same way that a human brain is private. I might analyse legal data and arrive at a tentative conclusion and then write down my reasoning for others to see but the explanation may or may not reflect what my brain actually did. Moreover, nobody knows if it actually reflects what my brain actually did. Including me. That's brains for you!
So the analysis logic is inside the box and to a degree hidden from view in the same way that humans cannot look inside brains to see what is actually going on. The law itself is outside the box and not hidden from view. It is a corpus of knowledge that is "out there". The analysis process itself is always tentative in its conclusions. The outcomes of courts are called "opinions" for a reason - not "answers".
The world of law not only tolerates but is actively architected to allow differing interpetations of the same corpus of law. Society deals with the non-determinism through an escalation process (appeals), majority voting (Many judges, same case, one judge one vote. Majority prevails.) and a repeals process (what is valid law today, might not be valid law tomorrow.)
Again, this is not a bug. It is a feature. It is a feature because as you may have noticed, the world is a messy place full of ambiguity and change and shifting views. Human behavior is a messy thing. Justiice/morality/the common good...these are complex concepts. The legal systems of the world have evolved in order to try to deal with the messy parts. Any computer system that gets involved in this has to engage with the reality that a lot of what sure looks like messy aspects in the world of law - especially to most computer programmers - are there for good reasons. They are not "bugs" to be fixed by getting rid of the English and replacing it with computer code.
Having said that I was going to focus on the data side first, I appear to have drifted off to the algorithm side somewhat. Oh well, best laid plans...
Coming back to the data side now, if all the data required for the legal reasoner is outside the box, then what is it? Where do we get it? Can we actually get at all of it?
We will pick this up in What is Law? - Part 3.
[1] https://en.wikipedia.org/wiki/Ignorantia_juris_non_excusat
[2] https://en.wikiquote.org/wiki/John_Adams
[3] https://en.wikipedia.org/wiki/Law_as_integrity
[4] https://plato.stanford.edu/entries/logic-nonmonotonic/