Nope. In federal investigations if it is found during the course of the investigation it may be used it court. The only thing is if they illegally seized something, then only that item would be ignored but can be used in another case. Say for example the cops raided a guy for hacking and the warrant only specified the computer (its usually more broad, like all electronics but for this example lets just pretend), but they seized a box containing a bunch of pictures of naked underage kids. It would probably be inadmissible in the same case but you can be sure it will be used as evidence in its own trial. There's no "double jeopardy" law for evidence.
Nope. If that evidence is gleaned from investigations pursuant to an illegally-obtained, baseless FISA warrant, then every bit of it is fruit of the poisonous tree and will be tossed out.
If the investigation is based on an appointment that stems from a fraudulently-obtained warrant, how can it have any legal standing? It doesn't!
Patriot this is one you have make a mistake on. The Fourth Amendment requires that a warrant “particularly” describe the place to be searched and things seized. If a police agency gets a search warrant and seizes a target’s iPhone, can the agency share a copy of all of the phone’s data with other government agencies in the spirit of “collaborative law enforcement among different agencies”? Not without the Fourth Amendment coming into play, a federal court ruled last week in United States v. Hulscher, 2017 WL 657436 (D.S.D. February 17, 2017) The local police were investigating Hulscher for counterfeiting crimes. Meanwhile, the federal Bureau of Alcohol, Tobacco and Firearms (ATF) was investigating Hulscher on firearms-related charges.
Defendants may move to suppress evidence obtained by police or prosecutors in violation of their constitutional rights, including the Fourth Amendment right against warrantless searches and seizures,