Google's chief executive Eric Schmidt has been targeted by privacy groups over the way the company allegedly fails to fully advertise its privacy policy.

The privacy groups, headed by the Privacy Rights Clearinghouse (PRC), have written to Schmidt accusing the Silicon Valley company of breaking Californian privacy law. They argue that Google must legally place a link to its privacy policy on its homepage.

Currently, interested parties must click on "About Google" and then scroll to the bottom of the resulting page to find the link.

Google has regularly been in the firing line on privacy issues. Campaigners have criticized it for the way it stores and uses individuals' information. Concerns have also been raised over Google Health, a hosted service launched last month which allows users to store and manage information regarding their health online. Critics say there is a risk individuals' medical information could end up in the wrong hands.

Fourteen privacy groups have signed the letter to Schmidt, which was published by the PRC yesterday. They are all organizations from California and Washington DC and include the Center for Financial Privacy and Human Rights, the Electronic Frontier Foundation, the Electronic Privacy Information Center and the World Privacy Forum.

In their letter, the privacy groups argued: "California law requires the operator of a commercial website to 'conspicuously post its privacy policy on its website.' The straightforward reading of that law is that Google must place the word 'privacy' on the web page linked to its privacy policy."

The groups said that nearly every major company places a link to their privacy policy on their homepage. They asked Schmidt to comply "as soon as possible".

Marc Rotenberg, executive director of the Electronic Privacy Information Center said: "This is not rocket science. The word 'privacy' is not going to take up a lot of space on the Google homepage."

Pam Dixon, executive director of the World Privacy Forum, said: "Consumers should be able to access Google's privacy policy with just one click from its homepage -- this is an industry-wide best practice that Google is not exempt from."

The letter to Schmidt claimed its reluctance to act was "alarming."

Google could offer no comment at the time of writing.