Picturing Factual Inference in Legal Settings

Abstract

There is an old saying that a picture is worth 10,000 - or 100,000 - words. But this is not true of every picture. There have been efforts in the past to use pictures to portray factual inference and proof in legal settings. These efforts, however, have met with limited success - and one of them was a spectacular flop. This paper takes another look at the role of visualization of problems of evidence and inference. It proceeds on the assumption that the use of pictures - the use of graphs, diagrams, and charts - to facilitate factual inference and proof in legal settings must be informed by the way the mind organizes its knowledge and acquisition of knowledge of the world. The paper argues that factual inference has four important general properties: the complexity and intricacy of marshaled collections of evidence, the diversity of evidence marshaling methods, the influence of time and change on inference, and the role of imagination and invention in factual inference. The paper argues that these four properties support the conclusion that computer-embedded procedures for the visualization of problems of evidence and inference are most likely to be useful and efficient if they support the capacity of actors in (actual or possible) legal proceedings to shift quickly between global, or synthetic, and granular, or analytic, perspectives on evidence and between different methods of marshaling evidence, and to see in the background, or in faint outline, marshaled collections of evidence that are not the focus of an actor's attention while an actor focuses on some other collections of evidence. There is reason to believe that without such flexible multi-layered techniques for looking at problems of evidence and inference, many proposed ways of picturing collections of evidence and arguments about evidence will be unappealing to prospective users and also inefficient.

Keywords: Evidence, inference, visualization, graphs, diagrams, charts