The Fifth Circuit has handed down a fascinating computer search case in United States v. Reddick. Here’s the question: If a private company runs a hash of a file and compares the hash to those of known images of child pornography, and it finds a match to a known image and forwards on the file to the government, is it a “search” for the government to then open the file to confirm it is child pornography? Held, per Judge James Ho: No, it is not a search under the private search reconstruction doctrine.
First, some background. The private search reconstruction doctrine lets the government recreate a private search as long as it doesn’t exceed the private search. The idea is that the private search already frustrated any reasonable expectation of privacy. Merely recreating what the private party did is within the private search and is not a new government search. But in the case of computers, that raises difficult issues: What is merely a recreation of a prior private search, and what exceeds the search?