Author Identification in American Courts

Abstract

Recent work has taken different approaches in attempting to use linguistics to identify the authors of documents by the style of their writing. Traditionally, linguists have sought to identify similarities and differences in a host of features, including spelling, syntax, word usage and others, and to draw inferences regarding authorship based on a comparison of those features. However, developments in the law of evidence in the United States during the past ten years have focused the attention of courts on the validity and reliability of a technique before an expert will be permitted to offer an opinion based upon it. Courts are especially mindful of whether a technique can identify an error rate with sufficient reliability. In this context, it is incumbent on the field to respond with methods that will be acceptable to courts. This paper discusses some significant achievements being made in meeting this challenge, including efforts to identify syntactic features that are diagnostic of authorship, eclectic methods that look for constellations of similarities, and the use of linguistic corpora, a development in which Malcolm Coulthard played a pioneering role.