It is a common practice among criminal investigators to "preserve" Internet accounts without cause. When an investigator learns that a suspect has a Facebook or email account, the investigator will direct the provider to run off and save a copy of the suspect's entire account and to hold it for the government. If, weeks or months later, the investigator can eventually develop probable cause, the investigator can come back with a warrant and order the provider to hand over the previously-preserved account files. And if the investigator never develops probable cause, the provider will usually realize eventually that the government isn't coming back, and it will usually then delete the extra government-ordered account records. This procedure is called "Internet preservation," and it's done in the name of a provision of the Stored Communications Act, 18 U.S.C. § 2703(f).
As regular readers know, I think the Fourth Amendment imposes limits on Internet preservation. First, the government ordering the provider to act makes the provider's act on the government's behalf state action, triggering the Fourth Amendment. Second, copying the account contents is a "seizure" of the account contents. And third, that warrantless seizure has to be justified as "reasonable" by having initial suspicion (typically probable cause) to justify the initial seizure and then the seizure occurring for only a reasonable period before a warrant is obtained. So I argued in my article, The Fourth Amendment Limits of Internet Preservation. And I backed up that article with a model brief for defense attorneys to file.
I'm pleased to say that at least a handful of motions to suppress have been filed based on my model brief. In several of those cases, the government avoided the merits by eschewing reliance on the preservation copy of the account. That is, instead of relying on a copy of the account that was only available when the preservation was made, the prosecution relied instead on files that were in the account when the government came to the provider with a warrant.
