Welcome to the final instalment of our short blog series on places you may not have thought to look for digital evidence.
- Biometric data
The use of fingerprints, retinal scans and facial recognition is no longer the stuff of science fiction. Its use may not be widespread yet, but it is certainly becoming a reality on a number of advanced devices.
Computers, laptops and mobile devices may be protected from unauthorised use by such biometric technology. If the data can be retrieved, it can help significantly with the attribution of that device – especially useful on mobile phones if cell site analysis is being carried out as part of the case.
It’s an emerging technology, so keep an eye on developments over the coming months and years. More and more evidential opportunities will present themselves.
- Near-field communications
This refers to technology such as the Oyster Card on London’s transport system, and credit cards are also being equipped with chips, which when waved near to a reader device can perform the same function as when it is inserted into a chip and pin device.
Such technology is also finding its way into mobile phones – the Google Wallet has been in the news recently (for all the wrong reasons – namely security issues). This is an app that enables users to pay for goods using their mobile phone using a near-field communication device.
Data may be recorded on the phone – including when it was used, where, and for what purpose. This could be a rich vein of potential evidence, and although its use is not widespread at the moment, it’s certainly worth keeping up with developments.
- Games consoles
Games consoles such as Xboxes, Playstations and Wiis now have web browsers as standard. They are much more than just a platform for gaming, with many allowing users to stream music over the internet, rent movies and interact with others online.
External hard drives can also be attached to consoles, enabling people to play music and movies from their collections through the console.
Consoles also enable instant messaging to take place, within games and simply via the messaging function in the console itself.
Use of all these features leaves a digital trail on the hard drive, making such devices a rich source of potential evidence.
- Throwaway culture
The focus has been on modern emerging technology, particularly smartphones. But it’s sometimes sensible to consider the other end of the scale: antique technology can also provide interesting evidential opportunities.
Many people tend to upgrade their handsets – and laptops and PCs – and put the old ones in a drawer or box. There they languish, gathering dust, until they’re needed for a criminal case.
It’s entirely possible to extract all sorts of evidence from these older devices, some of which can prove as tricky as the higher-end handsets and computers. Just because a phone or other device looks simple and cheap, the data it may contain could be crucial.
Here’s an example: CCL-Forensics used its web cache toolkit on a six-year-old Nokia 6230i handset and recovered 600 pages of web history – not necessarily the result you’d expect from a modest old device.
- With the network provider
A vast quantity of valuable evidence can be gathered from mobile phone network providers using cell site analysis. Network providers keep a variety of information about a phone’s use for a period of time – including the cell masts it used to make and receive calls.
This type of analysis can help to build up a picture of where the phone has been used, and can help in attributing different phones to their users – especially where criminals make use of “clean” and “dirty” phones. (Clean phones are those used for “normal”, everyday activities; dirty phones are those used in the course of crime, and are often thrown away afterwards.)
If a mobile phone has been used in crime, don’t discount the possibility that a wealth of evidence could be gathered using cell site analysis.
Here endeth our list of possible locations for digital forensic evidence – although it is, of course, not exhaustive. As technology advances, more and more types of digital evidence will become available for investigators.
CCL-Forensics’ R&D team keeps pace with new technology, developing tools and techniques for extracting this new data. If you have any questions, they’re always happy to chat. Just drop us a line at firstname.lastname@example.org.