Recent criminal psychology research has raised critical questions about applying non-verbal communication methods for lie detection purposes in forensic settings. Research has shown low correlations between non-verbal communication and deception. However, non-verbal communication methods are still widely applied and suggested by police manuals. Results obtained by experimental and field research are biased by the following factors: (i) attention is given only to quantitative aspects of non-verbal behavior; (ii) there is a lack of research of qualitative aspects related to non-verbal behavior analysis; (iii) lack of connections between non-verbal indicators and verbal content; (iv) lack of attention on timing of non-verbal behavior; (v) most research is performed on psychology students in experimental contexts. This article proposes a new methodology for applying the Facial Action Coding System as investigative support and not as a lie detection method. The Facial Action Coding System will be introduced to integrate with verbal content analysis and a new framework to interpret non-verbal signs discussed. The aid of standardized non-verbal methods will be discussed through an in-depth psychological analysis of a case of homicide perpetrated in 2010 in Southern Italy by discussing a video analysis of the suspects’ statements.