Although little known, the theoretical and methodological roots of lie detection, in particular of the development of the so-called "lie detector", must be placed in central Europe, in particular in Germany, Austria, and later in Italy at the turn of the 19th and 20th century. Focusing on Austria and Italy, we trace this development from Hans Gross in Austria to Vittorio Benussi and his pupil Cesare L. Musatti in Italy. Benussi, initially active at the University of Graz and later at the University of Padua, was the mediating link between the Austrian and Italian legal psychology tradition.
