From ACLU:
Can using privacy-enhancing tools (such as Tor or a Virtual Private Network) actually expose you to warrantless surveillance by the National Security Agency? This week, the ACLU sent off four FOIA requests to federal agencies in order to try and answer this question.To understand why we think that may be the case, we have to go back to the passage of the FISA Amendments Act (FAA) in 2008. That act was not a high-point for civil liberties or the rule of law. It included a provision giving immunity to the telecom companies that violated the law by assisting the NSA with its warrantless wiretapping program. Although the get-out-of-jail-free card given to the phone companies is the most well-known aspect to the FAA, there is much more to the law, and many other things that give privacy advocates reason to worry.Under the original Foreign Intelligence Surveillance Act (FISA), the government was required to provide specific, targeted requests aimed at foreign powers or their agents before lawful surveillance was permissible. But the FAA created an additional, broader surveillance system, enabling the government to conduct surveillance without particularized suspicion where a “significant purpose” is to obtain “foreign intelligence” and where the surveillance is targeted against persons "reasonably believed to be located outside the United States."