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Remote Methods for Volunteering Digital Evidence on Mobile Devices

NCJ Number
Date Published
December 2018
12 pages

Since investigations by law enforcement agencies often require obtaining digital evidence from mobile devices of victims or witnesses in a case, this report describes the “Disclose” system for the secure and selective submission of such digital evidence and a micro-service for creating and monitoring chain of custody for evidence obtained from the mobile devices of victims and witnesses.


Existing law enforcement tools used to collect evidence from mobile devices are designed for circumstances in which the device at issue has been legally taken from an alleged perpetrator of a crime; however, when witnesses and victims are requested to volunteer such evidence, they are often reluctant to share the entire content of their mobile devices. This requires that law enforcement investigators develop a method of collecting digital evidence from victims or witnesses in a selective and discriminant manner. The approach proposed in this report uses public key cryptography for signing and labeling evidence that creates records that enable defendants, civil society groups, and courts to verify the data collected by police. Retrieving information pertinent to a case without accessing all the miscellaneous information on a phone increases the chance of obtaining needed evidence while easing witnesses’ and victims’ privacy concerns. As described in this report, “Disclose” is an Android application that enables the selection, aggregation, and submission of digital information for law enforcement purposes. Users manually curate the evidence they wish to disclose instead of having to submit all information on the device. From the perspective of a persons who wishes to cooperate in a case, this application is a mechanism that securely and safety communicates relevant evidence while protecting privacy threatened by exposure of the entirety of the data on the device. 3 figures and 14 references

Date Published: December 1, 2018