This paper discusses the methods and results of determining links between telephone calls and certain events associated with a crime.
Telephone traffic data is information on telephone calls that is automatically stored at every telephone exchange. Such data includes caller phone numbers, IMEI (International Mobile Equipment Identifier) called phone numbers, date of calls, time of calls, duration of calls, and used base stations. Any disruption or change in the pattern of a person's routine calling within the time frame associated with a crime may be a useful area for investigation. In the case study presented in this paper, the telephone call data of a suspect revealed connections between the calls and certain crime-relevant events. All associations between the time of an event and phone calls during this time frame can be indications that the caller is involved in the event. The analysis used in the case study involved different methods, tables, graphs, and rules of association between calls and events. When groups of phone calls are characteristic for the time of the event at issue, it is logical to assume that the call groups are associated with the timing of the event, particularly when the calls do not reflect the pattern that precedes the time frame set for the event. All associations between the event time and some groups of phone calls can indicate that the caller is involved in the event. Attributes of the calls can provide further information on how the caller is involved in the event. 1 table, 1 figure, and 5 references