Digital evidence and procedural protections: potential of blockchain technology

Datafication of society and proliferation of cybercrime determine the unique importance of digital evidence in today's criminal proceedings. The integrity of data is crucial for their usability as evidence before the court; the traceability and ex-post verifiability of their lifecyde is necessary for the cross-examination on their validity as evidence. In digital forensics, the term chain of custody refers to a set of tools and practices aimed at guaranteeing the proper treatment of digital evidence and the accurate documentation of all the activities concerning its identification, collection, storage and analysis. The need to verify the correctness of digital evidence's treatment is made more urgent by the diffusion of highly intrusive detection instruments such as trojan horses, and by the increasingly transitional dimension of digital investigations. Therefore, the development of proper recording tools is crucial. The present work discusses how blockchain technologies could be deployed to maintain a transparent and tamperproof register of forensics activities shared among all private and public actors which participate to the digital evidence lifecycle. This instrument would facilitate national and international cooperation in digital investigations, guaranteeing both the integrity of data and the transparency of meta-information concerning their treatment. Ultimately, this would allow to better protect defendants' rights in relation to digital evidence.