Last week, a decision by a federal appeals court in California allowed law enforcement officers to secretly place GPS trackers under individuals' cars parked in private driveways without a warrant.
The judges with the Ninth Circuit court ruled against an appeal by a defendant interested in suppressing evidence gathered by officers who secretly attached a GPS device to his car without obtaining a warrant. The decision basically gave law enforcement officials in the nine Western states covered by the court the power to track individuals by GPS without probable cause, ComputerWorld reported.
But Chris Calabrese, legislative counsel for the ACLU, said the U.S. Court of Appeals for the District of Columbia Circuit ruled in the opposite direction on a very similar case in early August.
The D.C. court said that GPS tracking like that would violate the Fourth Amendment, which protects people against unreasonable searches and seizures, he said.
"The difference is in California, the court took the view that any time you move around in a public space you don't have an expectation of privacy," he said, "while the D.C. circuit said that there's a big difference between someone seeing you casually in public and the tracking and recording of your every movement over an entire month."
The California decision was not unanimous and some expect the case to go on to the Supreme Court.
In the dissenting opinion, Chief Judge Alex Kozinkski said, "1984 may have come a bit later than predicted, but it's here at last.
The thousands of e-mail messages living in your Gmail or Yahoo account also are fair game for the government.
In the 1800s, the Supreme Court ruled that traditional snail mail is protected by the Constitution, but that protection doesn't necessarily apply to electronic mail, the Center for Democray and Technology's Dempsey said.
"The government takes the position that all of the e-mail that you store -- in Gmail, Hotmail ... all of that falls outside the Constitution's protection and is available to the government without a warrant," he said.
The position dates back to the 1970s, when the Supreme Court ruled that records you give to a third party, including bank records, medical records, tax records and more, are not protected.
"You have zero constitutional privacy interests in records that you voluntarily disclose to a third party," he said.
Once an e-mail is stored in draft form or sent to a recipient, it's considered unprotected because you essentially had to turn it over to a third-party service to communicate it.
Dempsey said the same principle applies to text messages, wall postings on Facebook and other messages sent via third-party services, regardless of whether they're sent from smart phone or computer.
But though records stored in the so-called "cloud" by third parties are not protected, he said, records stored on your hard drive are protected by the Constitution.
"If the government wants to get your computer, your laptop, they do need a warrant, just like on "Law & Order," he said.
When it comes to technology-enable correspondence, your telephone conversations may provide your one last pocket of privacy.
As we know from endless movies and TV shows, it's technically possible to wiretap a telephone call and eavesdrop on a conversation, but Calabrese said telephone calls are protected by the Fourth Amendment and law enforcement officials have to meet a high standard to obtain a warrant.
"To wiretap a phone -- any phone -- requires a super warrant," he said.
Officials don't just need to prove probable cause, they need to show that they've tried getting information through other means and overcome other hurdles, he said.