01The question
Do the carrier records place the phone at the claimed address during the relevant hour, and with what certainty?
02Background
In a fictional matter, carrier call records (CDR) and a cell site list were delivered for one number over one day. The examination interprets them; it does not geolocate beyond what the cell data supports.
03Constraints
- A cell identity places a device within a sector that can span from hundreds of metres to kilometres.
- Records were delivered in local time; the offset was tested and declared before any conversion.
04Evidence received
05Examination method
Fix the time base
The cover letter stated local time; this was tested against a known event and the offset declared per file before converting every row to UTC with the original value kept alongside.
Separate real contacts from non-conversations
Forwarded legs, unanswered calls and voicemail records were marked so they would not be read as conversations. Data-session rows were treated as carrying a start cell, with movement possible before an end cell.
Map cells as coverage sectors
Each cell in the relevant hour was plotted as a sector using the azimuth and an estimated coverage radius for the area, not as a pin. Overlapping sectors were shown. The claimed address was marked to see whether it fell within or outside the served sectors.
Cross-check and state the uncertainty
Where a handset log was available it was compared with the carrier events. The result was expressed as whether the phone was within an area that includes the claimed address, with the sector size stated, rather than as a point location.
Call log (calllog.db)Call history (CallHistory.storedata)cdrWorkbench
06Findings
Possible
During the relevant hour the phone used a cell whose coverage sector includes the claimed address.
BasisThe cell is consistent with the address, but the sector also covers a wider area, so the record does not place the phone at the address specifically.
Established
The phone was active (in use) during that hour.
BasisThe CDR records contacts with times and durations for that hour.
07Limits
- A cell sector is an area, not an address; the records cannot narrow the phone to a specific building from this data.
- Carrier records show the phone's activity, not who was holding it.
- Internet-based calls and messages do not appear in voice/SMS CDR and are not part of this picture.
08Report excerpt
At 14:20–14:55 UTC the number shows three answered legs on cell ID 7742 (azimuth 120°). Plotted as a sector with an estimated coverage radius, that cell includes the claimed address but also covers roughly 1.8 km² around it. We therefore state only that the phone was within an area that includes the address (possible), and that it was in use that hour (established). The records do not identify the user.
09Lessons
- Plot cells as sectors with a stated coverage estimate, never as a single pin on an address.
- The honest finding is often "within an area that includes the address", not "at the address".
- Keep "the phone was active" and "the person was there" as separate statements with separate confidence.