This paper proposes a method for modeling legal rules from common law jurisdictions in terms of the authority commitments they create for future cases. The purpose of this method is to capture information necessary for automated inferences about the strength of existing legal authority in favor of, or against, proposed statements of law. This data would have two potential uses. First, from the point of view of a given court and date, it would be possible to resolve the authority status of each legal rule, thus resolving conflicts between contradictory rules. Second, if the set of legal rules applicable to a particular court could be determined, it would be possible to apply those rules in a simulation of litigation in that court. The paper provides an example of authority-based reasoning by modeling rules from two cases about suppression of evidence derived from warrantless searches and seizures, and then demonstrating simple inferences about the status of those rules in federal and state courts in California.

We present three new visualization front-ends that aid navigation through the set of documents returned by a search engine (hit documents). We cluster the hit documents to visually group these documents and label the groups with related words. The different front-ends cater for different user needs, but all can browse cluster information as well as drilling up or down in one or more clusters and refining the search using one or more of the suggested related keywords.