In homicide investigations, the growing availability of data results in an increasing amount of information and Persons of Interest (PoIs) that can be collected and incorporated during an investigation. This might result in information overload and increased tunnel vision during a homicide investigation. In this paper, we designed a system to support homicide investigations in such a way that it reduces information overload and tunnel vision. For evaluation purposes, we built a prototype that was filled with a fictional homicide investigation. A user study indicated that criminal investigators experienced a significantly low level of information overload and tunnel vision using the prototype. Moreover, the results showed acceptable usability and verbal statements indicated a largely positive attitude towards the prototype. This research clearly shows the opportunity to use interface design artefacts to support the prevention of information overload and tunnel vision.