The Judicial Branch
is where the laws and regulations created by the legislative and
executive branches make contact with the world at large. The most
common way to think of the judiciary is as the public forum where
sentences/fines for not abiding by the law are handed down and as the
public forum where disputes between private parties can be adjudicated by a neutral
third party. This is certainly a major part of it but it is also the
place where law gets clarified with finer and finer detail over time, in USA-style and UK-style "common law" legal systems.
I like to think of
the judicial
branch as being a boundary determinator for legal
matters. Any given incident e.g. a purported incident of illegal
parking, brings with it a set of circumstances unique to that
particular incident. Perhaps the circumstances in question are such
that the illegal parking charge gets thrown out, perhaps not. Think
of illegal parking as being – at the highest level – a straight
line, splitting a two dimensional plane into two parts. Circumstances
to the left of the line make the assertion of illegal parking true,
circumstances to the right of the line make the assertion false.
In the vast majority
of legal matters, the dividing line is not that simple. I think
of
the dividing line as a Koch Snowflake[1]. The separation between
legal and illegal
start out as a simple Euclidian boundary but over
time, the boundary becomes more and more complex as each new "probe"
of the boundary (a case before the courts), more detail to the
boundary is added.
Simple put, the law is a fractal[2]. Even if a
boundary starts out as a simple line segment separating true/false,
it can become more complex with every new case that comes to the
courts. Moreover, between any two sets of circumstances for a case A
and B, there are an infinity of circumstances that are in some sense,
in between A and B. Thus an infinity of new data points that can be
added between A and B over time.
Courts record their
judgments in documents known collectively as “case law”. The
most important thing about case law in our focus areas of USA-style
and UK-style legal systems is that it is actually law. It is not
just
a housekeeping exercise, recording the activity of the courts.
Each new piece of case law produced at time T, serves as an
interpretation of the legal corpus at time T. That corpus consists of
the Acts/Statutes in force, Regulations/Statutory Instruments in
force *and* all other caselaw in force at
time T. This is the legal
concept of precedent, also known as stare decesis[3].
The courts strive,
first and foremost, for consistency with precedents. A lot of weight
is attached to arriving at judgements in new cases
that are
consistent with the judgements in previous cases.
The importance of
this cannot be over-estimated in understanding law from a
computational
perspective. Where is the true meaning of law to be
found in common law jurisdictions? It is found in the case law! - not
the Acts or the regulations/Statutory Instruments.
If you are
reading an Act or a regulation and are wondering what it actually
means, the
place to go is the case law. The case law, in a very real
sense, is the place where
the actual meaning of law is spelled out.
From a linguistics
perspective you can think of this in terms of the pragmatics
counterpart to grammar/syntax. Wittgenstein fans can think of it as
“language is use”. i.e. the true meaning of language can be found
in how it is actually used in the real world. Logical Positivists
might think of it as a behaviorist approach to meaning. That is,
meaning comes from behavior. To understand what a law means – watch
what the courts interpret it to mean.
The meaning of the
law comes from how it is used in practice and that use comes from the
empirically observable behavior of the courts. I could be a staunch
advocate of my interpretation of the law at time T as written in the
Acts/Statutes and Regulations/SIs but if the caselaw supports a
different interpretation to mine, I will have an uphill battle
defending my interpretation in court.
There is a useful
computing analogy here too. Every programmer knows that there are
times when the quickest way to get to
the true meaning of a piece of
code is to run it and see what happens. In
the world of law, the
quickest way to get an understanding of the true meaning
of some
legislative material is to find how it has been treated in the case
law.
It is also a highly efficient way of getting to "truth"
because, at the end of the
day, it does not matter how many possible
interpretations might be valid for any
given point of law. What
really matters is how the courts have interpreted it in
the past.
Extending the
programming analogy a little bit. It is often easier
to figure out
what some code does in a particular set of circumstances by
looking
for a unit test that matches the circumstances of interest.
Extending
the analogy even further, any new tests added should not
invalidate the
existing tests and any code changes to acommodate new
circumstances should not invaldate any existing caselaw. In other
words caselaw behaves
a little like regression testing in software
development. The courts strive
to not "break" previous
judgements.
It will come as no
suprise that most lawyers place great importantance on caselaw
searching. It might come as a suprise that there is no central entity
that publishes
the official caselaw. Typically courts act
autonomously and publish their
own volumes of caselaw periodically.
Much of it, to this day, still on paper with
the paper being the
definitive source. I.e. if a court does produce paper plus
electronic
case law, the paper "wins" in the event of any
discrepency.
There is a long
history
going back to at least the Nineteenth century of third
parties acting as aggregators
of caselaw. Mostly notably, West
Publishing (now part of ThomsonReuters) and LexisNexis,
now part of
ReedElsevier. I think it is fair to say that the modern practice of
law in common law jurisdictions would not be possible if
practitioners did not have
the ability to rapidly search caselaw.
The sheer volume of
existing caselaw and the rate of creation of new caselaw is such
that without computers, the common law system would not be able to
function as it does today.
Most of the computational support to date
has been in the form of document production
and search/retrieval.
There are signs that that is changing now as machines start
to help
practitioners interpret the caselaw. This is a topic for another
day!.
It is important to
note that the corpus of caselaw is not purely accretive. Caselaw is,
from time-to-time, repealed and practitioners need to be careful in
citing caselaw to ensure that the cited caselaw is still considered
"good law". Again,
enter the computers and their search
capabilities. In particular a ubiquitous
legal term
"shepardizing"[4]
which refers to looking up a case to
find its status and find what other cases cite it and what other
cases it also cites.
The fact that
caselaw is not purely accretive creates yet another interesting “at
time T” issue. Any judgement the courts might arrive at, at time T
is necessarily contingent on the full corpus at time T. The exact
same issue, examined at some future time point T+1 might produce a
different result if some of the caselaw that was “good law” at
time T is no longer “good law” at time T+1. We will return to
this later on when we talk about defeasible logic and analogical
reasoning but they are best parked for now until we have finished the
survey of the sources of law itself.
It is in the area of
caselaw that our imagined virtual legal reasoning box runs
into its
biggest challenge with respect to access to the raw materials of
law.
In common law jurisdictions, the volume of caselaw that is
considered "good law"
at any time T is vast, goes back
centuries and is not available anywhere
as a single corpus.
Plus,
the best sources are in fee-based repositories.
The good news is
that the caselaw corpus is not homogenous in terms of its
importance
to precedent. In many interesting respects the caselaw corpus is
the
grand daddy of all Social Networks. Yes, you read that right. Social
Networks!
Cases are linked to other cases by means of a formal
referencing mechanism. A
commonly used set of standards for these
citations is known as the Blue Book[5].
The links between cases are
not randomly distributed. They are in fact a poster child for the
concept of a power law distribution[6].
Lawyers and judges
working with the caselaw corpus spend their time on the subset
of
cases that naturally follows from following citations. Cases that
that have high "rank" - where rank refers to the inbound
and outboud
connections to other cases – are very important cases, by virtue of the citation network around them. If this reminds you of
the original Google concept
of Page Rank you are exactly right.
Citations serve two primary purposes. Firstly,
they are indicative
of the relative importance of a case (“how often has this case been
cited positively in cases like mine?”) and secondly, they give
a
good indication of how robust a case is likely to be against repeal.
The
citation network can tell you a lot about the knock-on effect of
repeal and remember,
in common law systems, a really important
"logic" at work is the logic of consistency with previous
decisions.
There is an old
adage that it is not possible to step into the same river twice.
This adage capture my mental model of caselaw. It is like a fast
flowing river
with the added twist that over time, it can forge new
pathways and route around
obstacles, while continuing to be "the
same" river.
In fact, the entire corpus of law is like that.
It is constantly changing – every
day. Every new piece of caselaw,
every new regulation, every new act, adds new data points into the
fractal geometry of the previously mentioned Koch Snowflake of
legality.
Rivers are not easy
things to capture in databases! That is why, to my mind
, the key
challenge in regulatory data management is actually regulatory
change
management. In fact, I think of the two as being the
same thing.
Modelling the data is hard enough - as I hope you can
appreciate based on the
material presented here so far. Modelling
how the data changes and how any
computational system can be kept up
to date with the changes, is another matter completely. Regulatory
change is not something you can afford to park and
deal with another
day in any useful conceptual model of law. I would argue it
needs to
be the central plank of the data model of law. After all, if you have
a model
that works well when things change, it will work just fine
when things do not change.
But the reverse is not true.
So that is it for
caselaw for now.
Next up, we wrap up
coverage of the sources of law with some other sources not
yet
mentioned. We will also take a stab at summarising and classifying
the issues
related to accessing the corpus of law, covering all the
sources mentioned.
From there, we will
turn our attention to the legal reasoning process itself.
That is
where the fun stuff really starts. See
What is Law - Part 6.
-->