• by Wendy Davis , Staff Writer @wendyndavis, January 24, 2013

Google often comes under fire for its privacy practices, but the company also has at least one policy that's surprisingly privacy-friendly.

This week, Google revealed that it doesn't disclose email messages to law enforcement authorities unless they obtain search warrants. "Google requires an ECPA search warrant for contents of Gmail and other services based on the Fourth Amendment to the Constitution, which prevents unreasonable search and seizure," a spokesperson says in an email to MediaPost.

Google will disclose some metadata, like IP addresses, with just a subpoena. Still, the stance against disclosing content is notable because the Electronic Communications Privacy Act doesn't require search warrants for emails older than six months. Instead, when messages have been in storage longer than 180 days, ECPA only requires law enforcement authorities to get a subpoena -- which is easier to obtain than a search warrant. That's because judges can only sign search warrants if the authorities have probable cause to believe that a search will uncover evidence of a crime. But judges can sign subpoenas for any information that's relevant to a pending matter.

Whether the government should need a search warrant for emails has been the subject of much controversy recently. In one high-profile case, a judge in New York last year required Twitter to comply with a subpoena for the tweets of an Occupy Wall Street protester who had been charged with disorderly conduct. The judge rejected requests by Twitter and the protester to quash the subpoena, which was issued without any finding of probable cause.

Even more famously, former CIA Director David Petraeus resigned last year after law enforcement officials obtained emails that brought to light his affair with Paula Broadwell.

In November, a Senate panel cleared a bill that would revise federal law by banning the authorities from obtaining email messages without first convincing a judge to sign a search warrant. That proposal hasn't gone anywhere and its fate is uncertain.

In the meantime, Google adopted the search-warrant standard without waiting for new laws.  A Google spokesperson declined to elaborate on exactly how the company has avoided legal repercussions. It's possible that Google has gone to court to quash the subpoenas, but the company isn't saying whether or not it has done so.

Even though Google's move goes beyond what the ECPA requires, it's worth noting that one federal appeals panel said the constitutional ban on unreasonable searches and seizures trumps ECPA. In that case, the 6th Circuit Court of Appeals ruled that the police must obtain a search warrant before they can legally access email messages.