What do Microsoft and Yahoo have on their home pages that Google doesn't? They have links to their respective privacy policies.

To find a link to Google's privacy policy, you have to follow the "About Google" link from Google.com.

The absence of a privacy policy link on Google.com may seem inconsequential, particularly given that few people actually read privacy policies. But a number of privacy groups find the missing link to be "alarming."

Fourteen privacy groups, including Privacy Rights Clearinghouse, the World Privacy Forum, Consumer Action, the Electronic Frontier Foundation, Consumer Federation of California, and ACLU of Northern California, have written an open letter to Google CEO Eric Schmidt urging the company to add a link on Google.com to Google's privacy policy.

"California law requires the operator of a commercial Web site to 'conspicuously post its privacy policy on its Web site,'" the letter says. "The straightforward reading of that law is that Google must place the word 'privacy' on the Google.com Web page linked to its privacy policy. Moreover, just about every major company that operates a Web site places a link to its privacy policy on its homepage."

Aesthetic treason though it may be to clutter the nearly pristine Google.com with an additional seven letters, Google really ought to comply, even if doing so results in a slight statistical diminution of "user happiness" -- Google's measure of how pages perform. (Believe it or not, Google pays a lot of attention to tiny details that affect page load times and user response. Tenths of seconds matter to Google.)

Clearly, Google is not keen to set a precedent that anyone with a grievance is entitled to redress on its home page. But the company has to make sure its public statements about privacy remain consistent with its actions. And it just looks bad for Google to insist that it reads the law differently than everyone else. It makes Google look like it's trying to pull one over on its users.

Google's stance is particularly perplexing given that in 2005 and 2006 the company publicly resisted the U.S. Department of Justice's demand for user search data to protect user privacy. Google associate general counsel Nicole Wong said at the time in a blog post that Google worried that "if the government was permitted to require Google to hand over search queries, that could have undermined confidence that our users have in our ability to keep their information private."

What could boost user confidence in Google's ability to keep user information private more than a prominent privacy policy? (Aside from deciding not to store any user data for any purpose.)

At Google's recent developer conference, VP of search products Marissa Mayer said that the "©2008 Google" notice on the Google home page exists as punctuation, to alert users that the page has loaded completely. Why not replace it with a "Privacy" link, since the copyright notice isn't legally necessary?