Depends how you define "simpler." There would be a LOT of incredibly specific definitions, since there would be no room for interpretation by a judge.

Consider a law that says "you can't drive a vehicle without a license." Is a bicycle a vehicle? What if it has a motor and weighs a lot? A velomobile? What about a hovercar?

There might be 2,000 laws referencing "vehicle [definition #4,849, version 5]".

(Actually, I guess a sensible definition might be based on momentum: we'll call a tricycle a vehicle if you manage to get it going fast enough; the point is that you can hurt someone with it.)

There's a sub-area of AI, since about the 1970s, that does try to do that, but it's very much at the research level. Modeling even simple "common sense" things is notoriously hard for computers (commonsense reasoning seems to require a large amount of implicit background information), so it's not clear that easy to unit-test coincides well with a human notion of simplicity and predictability.

That's one reason that, in addition to being an interesting challenge domain for AI researchers, it's interesting to logicians, who aim to come up with logics and decision procedures that can capture what a decision procedure in law looks like (classical first-order logic and theorem-proving don't seem to model it well). The main short-term application is to reasoning-support systems that can suggest potentially winning arguments, point out obvious holes in draft arguments you were going to make, etc., sort of the legal analogue of medical diagnostic systems.

A classic paper from 1977: http://www.cs.rutgers.edu/~mccarty/research/hlr77.pdf

A more recent system aimed at interactive use: http://www.ai.rug.nl/~verheij/publications/pdf/ai2004.pdf

A book, albeit priced at the usual Springer price-point that assumes no non-library human will buy it: http://www.amazon.com/gp/product/3642064329/ref=as_li_ss_tl?...

> Yes, we should have black and white laws, and unit tests for them.

First problem: I don't think that can be done. I'd be a lot more convinced to consider arguments like this accompanied by completed samples in some real area of human endeavor of the "black and white laws" with accompanying "unit tests" (and, anyway, wouldn't we want automated user acceptance tests, not unit tests.)

The problem with this is, human beings don't blindly interpret and process laws as code. Human beings can honestly differ in their interpretation of a law, and the accepted interpretation can change over time.

Some one, or some body, would have to decide what the 'proper' interpretation of these laws would be, and craft the 'unit tests' such that they correspond to the status quo. Then that someone or some body would have to ensure that anyone who disagrees with that interpretation gets put down. What you're describing seems like a particularly technocratic form of fascism to me.

I think that's impossible with the current English language, and the fact that human beings disagree about lots of things.

No, you'd see more complex laws because law makers would just write around the unit tests rather than address the fundamental issue. Ergo, accessing a university computer would be fine (because that's in the test) but accessing a library computer would not .

> I believe we'd see a lot simpler laws.

Only if you model the domain with fuzzy logic. Otherwise you have a combinatorial explosion of specific definitions.

And guess what? That's already how the law works:

"Reasonable person similarly circumstanced".

"Beyond reasonable doubt".

"Balance of probabilities".

I'd love to see this for a subset of laws. You could start with the law surrounding permits, for example.