Fruit of the poisonous tree. The legal standards for what can be presented in court are higher than for what can be performed and use for counter-terrorism, mis

Fruit of the poisonous tree. The legal standards for what can be presented in court are higher than for what can be performed and use for counter-terrorism, missing persons investigations, hostage rescue, and all sorts of police/military/intelligence actions that aren't going to end up in a courtroom. Does anyone know the legal status of foreign intelligence agencies as far as probable cause? I don't think it'd be considered valid probable cause.