Although there are gods of Justice (in both Courts, actually), and a number of related gods, there is no universal, over-arching concept of justice that all cultures at least pay lip service to. There are, however, some over-arching themes, isolated largely by alignment as follows -
- Lawful cultures tend to have well-developed systems of jurisprudence, or (for less sophisticated and/or organized societies - certain tribes and the like) codified systems of behavior and cultural mores and rules. These laws may make no sense to outsiders - "In Unknown Kadath, no man may kill a Cat" and the like - but they exist, and are (to a greater or lesser extent) enforced.
- Neutral (re Law/Chaos) cultures often also have developed legal systems, but they are more often either looser in structure and enforcement, or to have other purposes than their mere alignment (re good/evil) might suggest. An example might be a jurisprudence system based on balancing actions and re-actions - at it's simplest, "An Eye for an Eye" - seeking only to redress harms done directly.
- Chaotic cultures - those few that exist - usually have at least some sort of legal system and code of law - but the system is very often either moribund, corrupt, or simply disrespected to the point of uselessness. Some chaotic systems are nearly (or are) anarchic in structure, relying on personal honor and codes of ethics to mitigate anti-social behavior. In a small handful of (mostly elven) societies on Malaster, this actually works.
- Good societies use their system of laws to both defend the public from abuse, and (in some cases) to level the playing field between the wealthiest and poorest to some extent - but this is only uncommonly found in larger societies.
- Neutral (re good/evil) societies tend to see the law as an arbiter and unaligned party in any dispute, favoring no side, and seeking only that the law be followed in its letter and spirit.
- Evil societies may well have very well developed legal codes - but this does not mean that they are evenly applied to all (or even any but the societies' enemies). Counting on the legal system to protect you in an Evil society can be a fool's errand.
These points on the two axes of Alignment combine to provide an overview of culture's possible legal system - but can be swung around to favor one or the other. So one Lawful Evil society might see their legal codes as unassailable, paramount, and to be evenly applied as written in all situations - but dreadfully tilted to favor the wealthy and powerful in their formation, and harsh and cruel in all situations, while another might have an extremely sophisticated legal system - that is ignored entirely when it suits the wealthy and powerful (although such a society might be sliding into Chaos).
The Three Falls legal system is, understandably enough, primarily concerned with matters of trade, contract law, right-of-way on the rivers and in the dam lift wells, etc. It is supposedly applied evenly to all, but those with a more discerning eye can see that while outwardly sound, peeling back the first few layers of the system reveals a fine patina of corruption that, while not omnipresent, certainly allows those in the know to sidestep many - although not all - rules, laws, and regulations, to a greater or lesser extent.