Google's bi-annual transparency reports are often lauded for efforts in making police and government surveillance of email and web activity more visible. As the company's most recent report shows, the frequency of these requests in the US is increasing rapidly, but we may not be getting the full picture. As a recent Computerworld report aptly points out, Google's reports don't cover the warrant-less requests made under the USA Patriot Act, the recently-renewed FISA Amendments surveillance law, or FBI-issued National Security Letters, all of which include gag orders that prevent internet providers and web companies from disclosing any information. Such surveillance programs are said to look through hundreds of thousands of Americans, and Google's reports would look significantly different if they contained information on these warrant-less requests. As the law stands, however, there's little reason to believe web companies will be able to release such data any time soon.

Joshua Kopstein contributed to this article.