There is also concern about how long the messages and the scanned data will be retained by the company.
The entry-level service is free and, at one gigabyte, offers much higher storage capacity than the free offerings of Yahoo! and Hotmail. It also inserts ads into e-mails – something that is already done on a random basis by other e-mail providers. However, Gmail takes this one step further, by scanning the content of the e-mail and incorporating targeted ads into the message.
This, say privacy advocates, is a clear breach of the e-mail user's privacy. Google counters by saying that the intrusion is disclosed to users at the start, and is detailed in its privacy policy:
"We serve highly relevant ads and other information as part of the service using our unique content-targeting technology. No human reads your email to target ads or related information to you without your consent".
The policy continues:
"We also may collect information about the use of your account, such as how much storage you are using, how often you log in and other information related to your registration and use of Gmail. Information displayed or clicked on in your Gmail account (including UI elements, ads, links, and other information) is also recorded. We use this information internally to deliver the best possible service to you, such as improving the Gmail user interface, preventing fraud within our advertising system, and better targeting related information".
This retention of data, relating to user details, content of e-mail, ads displayed, and click-through details, is the biggest concern for some who worry that it leaves open the possibility of all the data being linked together at some point in the future.
Google has not ruled out correlating the data at some point in the future. But it is unlikely to be the only party interested in looking at the information: enforcement agencies worldwide are pushing for more access to communications data.
Chris Hoofnagle, associate director of the Electronic Privacy Information Center, told Wired News that the service may also fall foul of a federal law on interception, the Electronic Communications Privacy Act.