"We find that the government did violate [defendant Steven] Warshak's Fourth Amendment rights by compelling his Internet service provider to turn over the contents of his emails," the court said in U.S. vs. Warshak.
Despite the decision, IRS attorneys have pointed out the ruling only applies to states under the appellate court, not the whole nation, according to the ACLU papers. As a result, subpoenas are still sufficient outside the court's jurisdiction.
Law enforcement agencies will seek subpoenas when there is a "reasonable possibility" that information sought is relevant to an alleged crime. The standard is much lower than "probable cause" required in obtaining a warrant.
While subpoenas may be easier to obtain for police, they shouldn't be used to skirt the Fourth Amendment, privacy advocates say. "The Fourth Amendment has never been about accommodating law enforcement's whim or making investigations easy for them," Wessler said.
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