The Fifth Amendment contains the due process requirements for search and seizure (warrants, usually, unless you're the Bush administration). There are a bajillion Supreme and lower court decisions in this area. No warrant is required for surveillance that does not intrude where you have an expectation of privacy. I.e. your home, your landline telephone conversations, etc. The things you do in public are fair game for monitoring by the FBI or any other interested government agency. Back in the 60's the FBI created files for all sorts of public and not-so-public figures. As I recall, a few years ago, they allowed people to request a copy of those files, and all sorts of ex-hippies like Ken Kesey got theirs just for fun.
The 5th Amendment pertains to the federal govt. The 14th extends the same restrictions to actions by state agencies.
Don't often get a question pertaining to my day job...
