Modern mobile smart phones including Androids and iPhones may store a range of potential location-based information, including WiFi point use, location estimations made by the phone (such as iPhone location points), logs of use of mapping application usage, health application logs (such as steps and floors climbed) and also even conduct their own WiFi , bluetooth, and cellular scanning.    Where this evidence is present, it may exceed the ability of cell site analysis.  As technology has moved on, cell site analysis is now often the location evidence of last resort.  

An IP address does not necessarily establish the physical location of a device or person. Although IP information may sometimes assist in identifying how a device or account was accessed, its evidential significance must be considered in context and alongside other available location evidence.

Location evidence may also be present within ordinary device and application data. For example, photographs may contain relevant metadata, while messages, emails, bookings or other records may provide evidence connecting a device or user with a particular location.

Most importantly, the accuracy of each source of location evidence is often crucial to consider, since although a mobile device may have a GPS receiver, the location evidence on a device may actually be approximating the location, based on the mobile and WiFi networks in the area or otherwise.  Hence, it is important to consider the limitations of what can be determined for each source in relation to the locations of a device.   It is also generally important to combine this with other device evidence, such as the steps/health information and other interactions with the device even to the extent of if the phone is picked up, its screen lit up etc. which all may be logged.

There may also be other forms of stored evidence such as application and Cloud location point data (see below).

Location data may be generated by applications running on a device and may also be stored within associated Cloud accounts, for example, applications such as Life360.  Other examples include Google Location History and mapping data associated with Google or Apple services.

The way this data has been generated and stored is important when assessing what it can reliably establish. Location information generated by applications usually relies on the core data storage by the device which means that the underlying data needs to be examined.  Experimentation with other devices to see what may happen is often not adequate and scientifically flawed.

This is due to the fact a phone may be estimated rather than directly measuring and the data it is using for this process should be considered, and its accuracy and limitations therefore need to be assessed on a case by case basis, before conclusions are drawn.

Trackers may be fitted internally by the vehicle manufacturer, installed as aftermarket devices, or supplied for insurance purposes such as black-box insurance systems.

Tracker systems may also be built-in to Tachograph systems providing even more location information within modern lorries. 

Vehicles may also now have synchronised use with phone applications, provided by car manufacturers and data may also be stored directly within the vehicle  computer system itself (telematics).  In all cases, this information may be used as evidence in cases in terms of the location of the vehicle, and also interactions with it, including things such as ignition events and even when doors were opened/closed etc., the speed of the vehicle, or when a phone device was in close proximity.

Users may also use Satellite Navigation (Sat Nav) units which can also be examined in order to establish locations/journeys of use and the accuracy of this information assessed.   

Modern cars are also now fitted with SIM cards, meaning that in the absence of other location information, it may be possible to perform cell site analysis.   

Digital tachographs replaced analogue tachographs and record information about vehicle use, including driving activity. Unlike later Smart Tachograph systems, traditional digital tachographs do not use GPS, they rely on other vehicle inputs, including motion and wheel-speed information.

Smart Tachograph 2 systems incorporate GPS based location information and record specified location and journey-related events.  However, this data is not continuous.   This means it is sometimes not obvious what data is being used at a given time.   Hence, this data must be examined to assess what data is in use and its limitations, and also to assess this in the context of the circumstances alleged in a case, to determine consistencies and inconsistencies.

Electronic tags may be used to monitor an individual's movements, including compliance with exclusion zones and curfews.  Modern tags may incorporate GPS functionality and generate location and event data that can be retained by the monitoring service.

Sam is able to ensure you have been provided with the correct and original data as well as appropriate statements.  She is able to analyse the location and other tag logging data from, when it is alleged a tagged individual has been involved in a further crime or other relevant event.   

Sam can evaluate the location of use including preparing full chronologies for relevant time periods.   She can also compare the tag evidence to other case evidence, including the use of a phone/cell site analysis in a co-location assessment.   She can fully assess consistencies/inconsistencies in the location evidence, calculate speeds, as well as calculate tolerances and error factors, establishing the evidence limitations.  

Global Navigation Satellite System (GNSS) is the overall term that encompasses all different types of satellite systems which are currently in use and used in the past to determine locations.

Technically Global Positioning System (GPS) is specific set of satellites owned by the US.   In fact the night sky has many different satellite systems (known as constellations) which can be used for determining location.

Although “GPS” is commonly used as a generic term for satellite-derived location, the underlying data may have been generated using one or more GNSS constellations. Establishing exactly how the location was generated can therefore be important when assessing its reliability.

Location data is sometimes treated as if it represents an exact position. In practice, the reliability of a location point depends on how it was generated, the device and system involved, the surrounding conditions, the data recorded and the way the information has subsequently been processed or presented.

It must always be considered and never assumed, if the data itself involves GPS or other location information.   For mobile phones and applications used via them, although the device may have a GPS receiver, it is unlikely to be using it all the time, and instead may be approximating its location.   Hence, it is important that the source of the data is established.

Where individual location points, speeds or timings are significant to a case, Sam assesses the underlying data and the operation of the relevant system, including the events immediately before and after the location in question, as well as assessing the full data available. This helps establish what the evidence can reliably show and what limitations need to be taken into account.

Sam can evaluate the 'best' source(s) of location evidence, involving computers, routers and mobile devices, cell site analysis and trackers/vehicles (see above) including determining the accuracy of the evidence and combining the evidential sources. SRC can also combine/assess this evidence to determine its accuracy and to provide chronologies of locations and general device use. 

Sam can also assess comparisons between sources of location evidence in order to assess evidence of attribution, including correlations and differences in the use.    For example, comparing the location points/cell site analysis of a phone and the movements of a vehicle's tracker.

Location evidence can involve large quantities of technical data, including hundreds or thousands of individual location points. Simply presenting those points may obscure rather than clarify the movements that matter to the case.

Sam's approach is to analyse the underlying data, identify the relevant movements and events, and present the findings in a clear chronology with appropriate explanation of the technical limitations. The objective is to ensure that the evidence is both technically accurate and understandable to the court.