Witnesses are often invited to help the police to solve a crime by trying to identify a perpetrator. However, it may not always be possible to identify a suspect based on their visual appearance. Indeed, in some cases, people only heard the perpetrators voice, but didn’t see his or her physical attributes. Under these circumstances the victims are seen as earwitnesses. Over the decades, more and more earwitnesses have been asked to identify a perpetrator in a voice line-up, which has then successfully been brought forward as evidence in court. It can make the difference between a guilty and innocent verdict in court. Judges often determine how reliable this testimony is based on the witnesses’ confidence rating in their choice. But are these earwitness statements always reliable fault prove? To answer this question, it is crucial to investigate whether changes in a perpetrator’s tone of voice between the criminal act and the following auditory line-up conducted by the police have an impact on self-rated confidence of participants. Therefore, our study tests in how far congruent (either angry or neutral during both the crime commitment and the police line-up) or incongruent (angry during the crime and neutral during the line-up or vice-versa) tones of voices affect the witnesses’ self-rated confidence.