A bundle of documents obtained through a Freedom of Information Act (FOIA) request suggests that the nation’s tax collector may have ignored a court ruling in 2010 that ordered it to always obtain a warrant before spying on emails stored on cloud servers, the American Civil Liberties Union (ACLU) said Wednesday.

The Internal Revenue Service (IRS), commonly thought of as accountants with the power to garnish wages and seize property, is also a law enforcement agency with the power to spy on communications, so it’s not totally surprising that it has typically followed Supreme Court precedent regarding law enforcement’s broad spying powers when it comes to emails more than 180 days old.

However, in a ruling issued December 2010, the Sixth Circuit Court of Appeals ordered the IRS to always obtain a warrant before rifling through emails, no matter how old, contained on services like Gmail and Yahoo Mail, which otherwise have significantly less privacy protections than, for instance, encrypted communications stored on a home computer.

The first indication as to whether the ruling truly made the agency change its ways came in January, 2011, the ACLU’s documents reveal. In an email titled after the case’s name, US v. Warshak, an IRS criminal prosecution attorney wrote: “I have not heard anything related to this opinion. We have always taken the position that a warrant is necessary when retrieving e-mails that are less than 180 days old.”