From: Threat Level
We Don’t Need No Stinking Warrant: The Disturbing, Unchecked Rise of the Administrative Subpoena
Meet the administrative subpoena (.pdf): With a federal official’s signature, banks, hospitals, bookstores, telecommunications companies and even utilities and internet service providers — virtually all businesses — are required to hand over sensitive data on individuals or corporations, as long as a government agent declares the information is relevant to an investigation. Via a wide range of laws, Congress has authorized the government to bypass the Fourth Amendment — the constitutional guard against unreasonable searches and seizures that requires a probable-cause warrant signed by a judge.
In fact, there are roughly 335 federal statutes on the books (.pdf) passed by Congress giving dozens upon dozens of federal agencies the power of the administrative subpoena, according to interviews and government reports. (.pdf)