This move is pitting the private companies against officials in law enforcement from the federal government, who say the company disclosures would be harmful to the investigations. It also adds to the increasing divide between Washington and Silicon Valley.
Officials in the government have asked the Internet companies to keep the subpoenas quiet voluntarily to avoid criminal suspects from being alerted.
The new policy will not likely have any direct affect on national security cases where government agencies are able to request information directly through National Security Letters that bar companies from disclosing.
It will not affect search warrants that federal investigators require to gain access to contents of user’s emails.
Civil liberty and privacy advocates hailed the changes in policy by the tech companies as a needed step forward to check on the government authority.
Legal experts have said the changes in tech industry policy could lead to the U.S. government seeking orders that prevent the companies from notifying the users of any subpoenas.
WordPress and Twitter Inc have already notified users of government subpoenas. In two different cases, the two companies were sent subpoenas from the U.S. government, which wanted the identification of users who had commented about politicians on blogs.
Prior to handing over the bloggers identities, both WordPress and Twitter notified its users, who then were able to fight the subpoena in a federal court.
In the case with WordPress, the government then withdrew its request, while in the case involving Twitter the individual involved revealed his identity to the government and had a private meeting with investigators who did not bring any charges.
Since July, Internet behemoth Yahoo Inc has notified its users when a subpoena is received and that has changed the way investigators work, said a Yahoo spokesperson.