Several relevant items for you this weekend.
Orin Kerr has this post at The Volokh Conspiracy. In part:
Computer searches usually happen in two stages. Agents take the computer, make a mirror image copy of its hard drive on a government storage device, and then search the image. Officers do this to ensure the integrity of the original data. Searching can alter the contents on the computer, so working from a copy preserves the original.
This two-step procedure raises an interesting puzzle for consent doctrine. What happens if a target consents to a computer search, the agents quickly make a copy, and then the target revokes consent before the image is searched? Everyone agrees that the officer can’t search the target’s own computer after consent was withdrawn. But can the officer search the copy? Is the copy now the government’s to search regardless of the suspect’s revocation, or should the revocation of consent cover both the original and the copy?
This is not an uncommon situation in military cases. I suspect we all have cases where the computer is taken and imaged, and then we send in a notice of representation and notice of withdrawal of consent.
And see also, Edward J. Imwinkelried (University of California, Davis – School of Law) has posted The Ambivalence in the American Law Governing the Admissibility of Uncharged Misconduct Evidence IProceedings of the Fifth International Conference on Evidence Law and Forensic Science, Forthcoming) on SSRN.