Many of the largest topics in worldbuilding are difficult to address in anything like a detailed fashion because they spread their tentacles through many other parts of society. In the case of law, these tentacles branch in two very distinct directions at once: first in the direction of government, and second in the direction of policing and judicial matters. So although the top-level concepts of law are rarely going to matter in a science fiction or fantasy novel, it’s worth taking a moment to perch at the junction of these things and take a look at the basic principles at play.
To begin with, we might note that law can generally be divided into two extremely broad categories: public law and private law. (The latter is also sometimes called civil law, but since that term also gets employed to mean something else we’ll be talking about shortly, I’m going to attempt to avoid terminological confusion.) Public law concerns the interaction between individuals and the State — capitalized here to indicate that the entity in question might be anything from an empire down to the local city government — and includes things like administrative law or penal law, i.e. “crimes” in the technical rather than colloquial sense of that word. Private law, on the other hand, concerns the interaction between individuals, and involves matters such as contracts and torts.
(Before I get any further, I should note: by necessity, these essays will contain some major simplifications, lest I bog down in a level of detail that will almost never play into a story. Also, my terminology is mostly going to default to American usage, because I’m from the United States — but I’ll diverge from that where necessary for clarity. One of the great challenges in addressing this subject is the wild thicket of technical jargon, much of which varies from location to location, sometimes in outright contradictory fashion.)
Very few writers are going to bother drawing up a description of the legal systems of their worlds, but there are two reasons to remember that this aspect of society exists. The first is that it can provide multiple avenues of conflict within a story, which is especially useful when one of those gets blocked: remember that O.J. Simpson was acquitted of murder in his criminal trial, but found “responsible” for the deaths of Nicole Brown Simpson and Ron Goldman in the subsequent civil (private) trial. Second, not every society draws the line between public and private law in the same place. In the modern United States, murder is a crime, i.e. a public law violation, because the government has decided that killing a fellow human being is an offense against the State . . . but historically, some legal systems have considered that essentially an offense between citizens, and have only gotten the State involved when the victim was royal or a State official or otherwise belonged to a particular important group.
The other thing to be aware of is what is mean by a “legal system,” and what that means for how a society adjudicates violations of the law. These days nearly the entire world can be classed under one of two systems: common law or civil law (here not used in the sense of private law), with religious law forming a third, less widespread category. Of course, that tidy picture falls apart near-instantaneously because countries can and do hybridize the systems in various ways, and the finer points of what distinguish them can be difficult to see from the outside. We can, however, still take a moment to look them over.
In a civil law system, a judge presiding over a case looks first to the legal code: a book (or more commonly, a whole set of books) that lay out how disputes should be adjudicated. Unlike the infamous line from Pirates of the Caribbean, this code definitely consists of actual rules, not mere guidelines — but since the rules can’t possibly cover every possible specific scenario, there will be times when the judge has to interpret how they should be applied. To do this, they generally look to the opinions of legal scholars, who play a very large role in shaping how the law gets applied.
By contrast, a judge in a common law system will also consult the legal code first — but when the application of that is ambiguous, instead of turning to the opinions of scholars, they will look at case law, a.k.a. judicial precedent: previous decisions made in comparable cases. How binding those decisions are is variable and dependent on circumstances far too complex for us to get into here, but the general takeaway is that judges play a more direct role in affecting how the law will be interpreted going forward.
A religious law system — which includes Jewish halakha, Islamic sharia, and (sort of) Christian canon law — more closely resembles civil law than common. It too draws on a set document, in this case a sacred one rather than legislative, and relies on the opinions of legal scholars to guide interpretation. The key difference here is that unlike a legal code, religious law is not often subject to amendment, expansion, or repeal; the text is usually fixed (though its interpretation can change over time). Religious law countries are less common nowadays, especially without hybridization with another system, but in some jurisdictions, believers are permitted to opt for settling their disputes in a religious court, especially in areas like marriage and divorce.
Finally, I should note that there’s also customary law. This doesn’t always get counted among the systems because it’s the least formalized: customary law is based on community standards, and often isn’t written down. But if you’re writing about a tribal society, for example, this is the kind of law they usually follow. The person presiding over the case will often be the tribal leader or some kind of revered elder, and they’ll base their decision on tradition and community values, rather than formal statutes.
In actual practice, these various systems may wind up looking very similar. In particular, civil and common law are going to arrive at the same place in the end, with the differences between their paths mostly being of interest to specialists. And every practical instance of a legal system will be shaped by the history and culture of the country where it’s used, so that no two are identical.
But I do want to keep sight of one thing, which is the cultural foundations underpinning the systems. Common law systems (which cover maybe a third or so of the world today) derive their body of precedent specifically from British practice, and civil law systems derive their codes specifically from continental European practice. The ultimate roots of the latter are in Roman law, but with major subdivisions based on Napoleonic law, Germanic law, and so forth.
These are not historical accidents; they show the effects of colonialism worldwide. Up until the fall of the Qing Dynasty in the 20th century, China had a completely different legal code based heavily on one originally promulgated in the seventh century, and India used to have traditional Hindu law, based on the Vedas. I’ve also mentioned Louisiana, which (thanks to its French heritage) is kind of a civil-law cake with common-law frosting on top. A fictional world might have its own diversity of systems — or if you have an ancient fallen empire, as so many fantasy worlds do, different countries might share similar legal frameworks inherited from that political ancestor.
There’s also the question of how this stuff plays out in the actual courtroom. People often speak of common law as being synonymous with the adversarial system of litigation, and civil law as being synonymous with inquisitorial litigation, because in daily life that’s often true. But they aren’t quite the same thing, and so next week we’ll turn our attention to what happens when people get in front of a judge.