Behind the rising pressure for the fullest use of new technology and surveillance is homeland security. As police and intelligence agencies seek to deter future terrorist threats, the government is testing the limits of the expanded authority Congress provided when it passed the Patriot Act with broad bipartisan support in October.

"The amount of subpoenas that carriers receive today is roughly doubling every month -- we're talking about hundreds of thousands of subpoenas for customer records -- stuff that used to require a judge's approval," said Albert Gidari, a Seattle-based expert in privacy and security law who represents numerous technology companies.