Working closely with a consortium of 15-plus police forces from around the UK (led by the Centre for Policing Research and Learning at the Open University), we are developing novel methods and software tools for supporting digital forensics in the context of policing.
Our current research focus is on evidence handling methods for forensic evidence from the social media. In particular we are investigation the following research question: How can witnesses, victims and suspects give evidence from their social media accounts to police investigations in a forensically-sound way while preserving user privacy?
With forensic-soundness we mean if evidence is modified or omitted by any party, it can be discovered automatically. With user privacy, we mean that the user never has to reveal more than what the police investigation needs to know.
In addressing the research question, we first designed a communication protocol called VLD (Verifiable Limited Disclosure). Using cryptographic hash function and public key encryption, it enables users of social media services and the police forces to exchange and handle privacy-sensitive information in a forensically sound way. We have implemented a Facebook application (called “social-lift”) based on VLD. The application allows Facebook users to send parts of their timelines to police forces. We are currently improving the user-friendliness of the tool so that it can be trialled by the Gwent Police in the coming months.