The Ninth Circuit recently heard an appeal that challenges a common tool of law enforcement: “f” letters.

Under section 2703(f) of the Stored Communications Act, law enforcement may compel providers of “electronic communications services” (think Google) to preserve “records and other evidence” (think email) for a period of time. These preservation demands do not require any degree of suspicion, let alone probable cause, and are sent without judicial approval. Here’s a sample, provided by the Department of Justice:

Because the statute allows law enforcement to bypass judicial review, “f” letters are an increasingly popular avenue for obtaining digitally stored, incriminating evidence.

Google, for instance, has annually received tens of thousands of “f” letters since July 2014. In the first half of 2018, Google received nearly 10,000 such preservation demands affecting over 24,000 users/accounts. (By comparison, during that time, Google received 8,687 search warrants and 11,099 subpoenas). In the second half of 2018, Facebook received 57,000 preservation demands affecting 96,000 users/accounts.

The use of “f” letter is becoming increasingly common. In its latest Transparency Report, Google published a graph depicting this increase. (The brown indicates preservation letters, the red are subpoenas and the gold, search warrants.)

Similar graphics provided in Facebook’s transparency report tell the same story.

Back to Basey. In Basey, law enforcement sent an “f” letter to Yahoo!, requiring that Yahoo! copy and preserve data from Basey’s account. Yahoo! complied (as it must under the statute). About 9 months after the “f” letter, the FBI returned with a search warrant and uncovered incriminating evidence. After being convicted at trial, Basey appealed, arguing that the government’s section 2703(f) preservation request violated his Fourth Amendment right to be free from unreasonable searches and seizures. The ACLU filed an amicus brief supporting Basey, and, at oral argument, the ACLU argued first.

The ACLU’s argument went something like this: When Yahoo!, acting as law enforcement’s agent, copied and preserved Basey’s electronic communications, they “seized” his property. Per the ACLU’s amicus brief:

Yahoo!’s compliance meant that Basey could no longer exclude the government from accessing, searching, using, or sharing his private messages and associated data. It meant that he could no longer delete his messages. Because of the receipt of the 2703(f) letter, whatever the user did to his information, a copy would nevertheless remain for government use. That copying and preservation meaningfully interfered with his possessory interests—and thus constituted a Fourth Amendment seizure

This argument apparently comes from Professor Orin Kerr. In a 2016 article, Kerr lays out the argument and its weaknesses, and concludes that “it’s a significant argument that defense lawyers should be making.” (Though, he cautions: “Perhaps I’m more of a fan of the argument because I came up with it; originating credit can blur vision.”)

Based on Monday’s oral argument, however, it appears that the practice of sending “f” letters will continue to go unreviewed. Basey moved to suppress the data obtained from Yahoo! after the court-imposed deadline. As a result, the district court declined to hear the motion. And the district court’s decision is reviewed for abuse of discretion.

Most questions from the three-judge panel went to procedural obstacles—and not the merits of the constitutional argument. In addition to Basey’s untimely filing, because the district court did not hear the motion, the record is lacking as to whether Yahoo! actually did copy Basey’s emails in response to the FBI’s demand, or whether Yahoo! preserves such data as a matter of course. So, the practice of “f” letters may continue to go unreviewed by federal appellate courts.