Google since 2009 has seen a more than 70 percent increase in requests from governments worldwide for information about its users and their possible criminal activities, according to Google's latest biannual "Transparency Report" on such requests.

For the six-month period ending Dec. 31, 2012, Google received 21,389 government requests for information about 33,634 users, including 8,438 requests involving 14,791 users by the United States government, according to a Jan. 23 post by Richard Salgado, legal director of Google's Law Enforcement and Information Security unit, on the Google Public Policy blog.

"Today we're releasing new data for the Transparency Report, showing that the steady increase in government requests for our users' data continued in the second half of 2012, as usage of our services continued to grow," wrote Salgado.

Google has been compiling and releasing the reports since 2010 to keep the process transparent for users of its services so they can have insights into what is done with the data stored by Google. "We've shared figures like this since 2010 because it's important for people to understand how government actions affect them," wrote Salgado.

In the United States, the number of government requests is up since the last Transparency Report that detailed January through June of 2012. In that report, there were 7,969 total requests involving 16,281 users.

Google complied with 88 percent of the government inquiries in the second half of the year and 90 percent of the inquiries in the first half of the year, the report states.

The latest biannual report includes more information than past versions, wrote Salgado. The reports will now include a breakdown detailing what legal procedures U.S. government agencies took to seek the information, whether it is through subpoenas, search warrants or court orders.

For the period from July through December 2012, 68 percent of the requests Google received from U.S. government entities were through subpoenas, wrote Salgado. "These are requests for user-identifying information, issued under the Electronic Communications Privacy Act (ECPA), and are the easiest to get because they typically don't involve judges."

Another 22 percent were through ECPA search warrants, which are typically ordered by judges,based on probable cause that a crime has been committed, he wrote.

The remaining 10 percent mostly involved other court orders.

This was the sixth biannual transparency report issued by Google. No specific requests or information are presented in the reports.

Jeffrey Child, a privacy expert and associate professor of communications studies at Kent State University, said the reports are illuminating and should give pause to Internet users who believe that what they do online is private and will not come back to haunt them.

"I think that a lot of people don't know about the extent of the inquiries here, about just how many requests that they get," said Child. "Litigators seek the information as they try to make a case that people communicate in every possible way as they seek information, through the Internet and Google searches. If they can have this information, they can make better decisions and they can make sure that they are prosecuting people in the right way."

That's a good thing, he said, but at the same time, "more people need to take note of it because it will cause more people to be cautious about what they do or say or search online. They may be think that that is private information and based on these reports, it is not and that information can be handed over" to law enforcement agencies when warranted.

"This is a great example of seeing the difference between people's expectations of privacy and the legal or the behavioral [side] where people might think that some of this information could never be turned over. If they knew that it could be turned over, perhaps they wouldn't do it."