In a landmark decision issued today in the criminal appeal of U.S. v. Warshak, the Sixth Circuit Court of Appeals has ruled that the government must have a search warrant before it can secretly seize and search emails stored by email service providers. Closely tracking arguments made by EFF in its amicus brief, the court found that email users have the same reasonable expectation of privacy in their stored email as they do in their phone calls and postal mail.

EFF filed a similar amicus brief with the 6th Circuit in 2006 in a civil suit brought by criminal defendant Warshak against the government for its warrantless seizure of his emails. There, the 6th Circuit agreed with EFF that email users have a Fourth Amendment-protected expectation of privacy in the email they store with their email providers, though that decision was later vacated on procedural grounds. Warshak's appeal of his criminal conviction has brought the issue back to the Sixth Circuit, and once again the court has agreed with EFF and held that email users have a Fourth Amendment-protected reasonable expectation of privacy in the contents of their email accounts.

As the Court held today,

Given the fundamental similarities between email and traditional forms of communication [like postal mail and telephone calls], it would defy common sense to afford emails lesser Fourth Amendment protection.... It follows that email requires strong protection under the Fourth Amendment; otherwise the Fourth Amendment would prove an ineffective guardian of private communication, an essential purpose it has long been recognized to serve.... [T]he police may not storm the post office and intercept a letter, and they are likewise forbidden from using the phone system to make a clandestine recording of a telephone call--unless they get a warrant, that is. It only stands to reason that, if government agents compel an ISP to surrender the contents of a subscriber's emails, those agents have thereby conducted a Fourth Amendment search, which necessitates compliance with the warrant requirement....

Today's decision is the only federal appellate decision currently on the books that squarely rules on this critically important privacy issue, an issue made all the more important by the fact that current federal law--in particular, the Stored Communications Act--allows the government to secretly obtain emails without a warrant in many situations. We hope that this ruling will spur Congress to update that law as EFF and its partners in the Digital Due Process coalition have urged, so that when the government secretly demands someone's email without probable cause, the email provider can confidently say: "Come back with a warrant."