Cellular Technology Forensics and Call Detail Records: It has become very common in many types of cases for one side or the other to claim that a person can be located using call detail records and cell tower locations using such terms as cell tower tracking, or cell tower triangulation.  The first thing to understand about this type of evidence is that it is commonly misused and mis-represented as to the accuracy of the location data.  Cell tower coverage can span an area of several square miles, meaning that the most accuracy you can get for locating a cell phone from  historical call detail records may be hundreds of acres, not one acre. One of the most important things to remember is that a cell phone cannot be located from a historical call detail record.  The best that can be done is that the phone can be placed in a general area corresponding to a cell tower that was connected to the phone at a particular time as a call was made or attempted. This kind of evidence is fraught with potential misunderstanding by courts and juries alike and should be treated accordingly. With the introduction of the E-911 services, cell phones can be located with varying amounts of precision, provided that the cell phone dialed 911.  Even in the case where a cell phone is used to call 911, the ability to locate that phone can still vary by a large amount.  For instance, in a phase I E-911 call scenario, the only information required to be provided by the phone company is the calling number and the cell tower location.   If the E911 call is a Phase 2 call, then there is a good likelihood that the cell phone location will be accurate to several hundred feet.