"What the government is allowed to know about you," isn't useful either since the government is allowed to know anything about you. The issue is how the govern

"What the government is allowed to know about you," isn't useful either since the government is allowed to know anything about you. The issue is how the government learns it. The 4th amendment only protects against information within a reasonable expectation of privacy. The Supreme Court has found that information turned over to a third party (like the phone company) no longer has a reasonable expectation of privacy. The general idea is that if you turning over data for a third party to read it is not private data. Things like email and text messages are private because they are kept private from even the business. However, there will be major issues in the future because of some of the practices that tech companies have engaged in. Google, facebook, etc. do not keep your private email and messages actually private. They data mine the shit out of it. There will eventually be a case that argues Gmail falls under the third doctrine. The tech community will be outraged at the government overstep. But the real problem is the tech corporate communities total disrespect of the their users privacy.