Interesting Article on United States v. Collins, Case on Ex Ante Limitations on Computer Warrants

In a recent article, Ex Ante Regulation of Computer Search and Seizure, 96 Va. L. Rev. 1241 (2010), I wrote about the relatively new practice some magistrate judges have adopted of imposing ex ante restrictions on the scope of computer warrants that control how and when the computer is analyzed after it is retrieved from the place searched. has an interesting story about litigation in federal district court in San Franscisco about a dispute over one such restriction.

The story isn’t great on the details, but a quick look at one of the reported cases on Westlaw suggests that the feds obtained 27 warrants to search and seize a bunch of computers in this wide-ranging conspiracy case. After executing the warrants, the feds retrieved over 100 computers to search back at the government’s lab. Many but not all of the warrants contained the following restriction: “Within a reasonable period of time, but not to exceed 60 calendar days after completing the forensic review of the device or image, the government must use reasonable efforts to return, delete or destroy any data outside the scope of the warrant unless the government is otherwise permitted by law to retain the data.” In the current dispute, the defendants are arguing that the government has to return/destroy all non-pertinent data on the computers now based on the language of the warrant restriction. On the other hand, the government is arguing that it has a right to retain image copies of the hard drives so it can establish the involvement of each of the defendants and fend of claims that it tampered with the original data on the hard drive. The opinion by Magistrate Judge Paul Grewal concluded that after the government obtains a warrant for a computer it has no right to retain information stored in the computer that is not relevant to the case, and therefore that “the government must endeavor to give back to the defendants data outside the scope of the warrants” using “reasonable effort that minimizes the government’s exposure to non-targeted documents.” The government has now appealed to District Judge Lowell Jensen.

I haven’t taken a close look at all the documents in this case to know the details of what the parties are arguing, but my own view is that these sorts of ex ante limitations on warrants are not permissible in the first place. As a result, I don’t think the restrictions have legal force, and relying on them to determine the scope of the rights here therefore doesn’t make much sense. More broadly, there’s a lot of case law on Rule 41 motions for the return of property, and the general view of the precedents is that the government can retain the evidence pending trial if it has a plausible case for a need for it at trial. I suppose the issue here should be how to apply those general principles to computers: Do you see the relevant files on a hard drive as as distinct entities from the irrelevant files, and at what level of granularity? And how do you know which files are relevant, as the defense attorneys will be very tempted to say that the destroyed files ended up destroying exculpatory material– making files that seem irrelevant now appear very relevant later? Interesting issues. And ones made particular complicated in the Ninth Circuit thanks to the confusing Comprehensive Drug Testing precedent, so it will be interesting to see what the district court will do. Stay tuned.