From Security Focus, something to chew on:
The Google subpoena fight isn’t really about the anonymous data at issue here today. It is really about the way the government can “deputize” unwilling private companies who collect and maintain massive databases to act as their agents in the future. Want someone’s credit report? Don’t subscribe to Experian and subject yourself to the Fair Credit Reporting Act, just whip out a subpoena. Want to engage in massive warrantless domestic surveillance of e-mail communications? Don’t mess with FISA, Title III, ECPA, or even any Presidential inherent authority. Just pass a law (like the ones just passed in Europe) mandating that ISPs and phone companies retain such data, and then subpoena not just one person’s emails, but everyone’s – as long as it is relevant to some issue in some litigation somewhere. Let’s just create a single massive database of what everyone is doing all the time, and let anyone “dip” into it whenever it is deemed to be relevant to settling some dispute.