WASHINGTON, August 14 (RIA Novosti) – Google has made it official, casually acknowledging what many people already knew or at least suspected: emails sent through its free Gmail service will be “processed” with no guarantee of privacy.

"Just as a sender of a letter to a business colleague cannot be surprised that the recipient's assistant opens the letter, people who use web-based email today cannot be surprised if their emails are processed,” by the recipient's e-mail service provider in the course of delivery,” said attorneys for Google in a court brief.

“Indeed, a person has no legitimate expectation of privacy in information he voluntarily turns over to third parties," they added in the June motion to dismiss a class-action data-mining lawsuit.

The motion refers to a 1979 US Supreme Court ruling about the warrantless gathering of information from electronic communications, in that case a telephone call routed through a phone company.

Google argued the ruling still applied to email communications sent and received today.

The company has admitted using an automatic scanning system to filter spam and to provide customer-specific ads to consumers. Google also said its consumers are informed about privacy and other issues when they sign up for the service and consent to its privacy policy.

But some privacy advocates are outraged.

The nonprofit public advocacy group Consumer Watchdog (CW), which obtained the Google court brief, said Google’s analogy about a letter sent through the US Post Office was “wrong-headed.”

"I expect the post office to deliver the letter based on the address written on the envelope. I don't expect the mail carrier to open my letter and read it. Similarly when I send an email, I expect it to be delivered to the intended recipient with a Gmail account based on the email address; why would I expect its content will be intercepted by Google and read?" said John Simpson, director of CW’s Privacy Project, in a statement on the group’s website.

“Google has finally admitted they don’t respect privacy… If you care about your email correspondents’ privacy don’t use Gmail,” he added.