Visualisation of legal information is gathering momentum, albeit in baby steps. Without a doubt, Justis have been responsible for the pushing the envelope further than anyone else in this respect (see their Precedent Map in JustCite and text heat mapping in JustisOne).
Text visualisation tools almost certainly have a bigger role to play in the provision of online legal information. The challenge is to make sure that they are genuinely relevant and that the trends they describe are accurate.
One facet of legal information that is ripe for useful visualisation techniques is the mapping of how a case has been treated by subsequent cases. The Justis precedent map runs along these lines: the case under analysis appears as the central node in a sort of clock dial. The nodes in the left hemisphere of the dial are the cases that have been considered by the case at the central node. The nodes in the right hemisphere of the dial are that cases that have themselves considered the case at the central node. Colour-coding is also used to denote the class of consideration, e.g. positive, negative etc.
There is a potential use-case in which a user might wish to view the "authoritative profile" of a particular decision in a way that is not neatly satisfied by the Justis precedent map or any other tool I'm aware of. Say, for example, I wanted to form a bird's eye view of a particular case's authority profile in order to help me make an assessment as to whether it is good authority for some line of argument I'm seeking to run. What I want to be able to see, at a glance, is the rough shape of how that case has been treated by later cases. With this in mind, I tried to develop an extremely rough and ready visualisation that could assist in this situation.
Plotting instances of subsequent consideration on a radar chart
The solution may or may not be something that runs along the lines of the radar graph below.
The graph works by plotting points on a radar chart that correspond to the frequency over time a case has received a particular class of subsequent consideration. The classes of consideration (e.g. applied, distinguished etc) that run around the chart area are based on the granular consideration matrix developed by The Incorporated Council of Law Reporting for England and Wales. The right hemisphere consists of "positive" treatment classes, the left hemisphere consists of "negative" treatment classes.
The larger the area of shading in the right hemisphere, the more positively the case has subsequently been treated. Conversely, the greater the area of shading in the left hemisphere, the more negatively the case has been subsequently treated.