The present study attempts to investigate the nature of the work of the forensic linguist to find out the procedural methods used to attribute authorship of texts to their potential owners. The aim is to examine the aspects of the linguistic theory on which the work of the forensic linguist depends, and upon which he may base his assumptions and then verify their validity. To achieve this, the study follows the narrative analysis method, one of the methods of qualitative approach in humanities, which depends on the analysis of the text and tracing the human experience of the forensic linguist in his work and obstacles he encountered. The study deals with three famous cases that occupied the Western judiciary for a period of time. The first is the issue of doubt in the statement of the culprit known as the case of Derek Bentley in Britain, the issue of comparing manuscripts known as the Unabomber, and the issue attributing part of a text to one of its co-authors. It is hoped that the study of these three cases will lead to further research in this neglected area of science in the Arab world.