What Google's Transparency Report doesn't tell us

Transparency reports are basically a biannual compilation of requests Google receives from governments around the world for Internet user data. The reports, which have been generally lauded by privacy experts, are an effort by Google to keep users informed about the data requests and how often it complies with them.

The company's latest report, released on Wednesday, shows that the U.S. government again led other nations in submitting the most requests for user data with Google. In the second half of 2012, the U.S. put in 8,438 requests for Internet user data, up 6% from the 7,979 requests it placed in the first six months of the year.

Between 2011 and 2012, U.S. data requests from Google increased by more than 30%.

More than two-thirds of the data requests from the U.S. government were by subpoenas issued under the Electronic Communications Privacy Act (ECPA) that did not require any kind of judicial oversight. Only about 1,900 of the requests had probable cause warrants attached to them. Google complied with close to 88% of the requests it received from the U.S. government.

Sobering as the numbers are, they do not tell the full story, according to privacy advocates and rights groups.