Even though Berthold Brecht is considered to be one the most important German play-wrights and drama theorists of the twentieth century, and his work is still performed all over the world, and his concept of epic theatre draws the attention of a large number of experts in the field of drama, many critics believe that the future will remembered him primarily for his lyrical works. His lyrical work is not easily understood by itself, so it should be viewed relative to the tradition that it develops and criticizes at the same time. In this way one should also interpret the ballad selected to be the theme of this paper. In the study that we have started as the main subject of the paper, we have set up a reconstruction and solving of the crime in Brecht's ballad 'On the Infanticide Marie Farrar'. To achieve the goal set in this paper, namely, shedding light on the crime committed by Marie Farrar, we first have to define the investigative discourse as well as its relation to the literary discourse. The interaction between these two discourses opens up new horizons in interpreting and comprehending this crime. By reading literary traces we will try to shed light upon the crime, for which we sense was 'written between the lines' and which was the direct cause of the crime committed by Brecht's juvenile anti-heroine.