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Citizens traveling public highways should have no expectation of privacy just because police are tracking their movements through GPS rather than in person, the U.S. government argued Tuesday in a case before the Supreme Court that pits the interest of law enforcement against individual privacy rights.

The dispute springs from a situation in which police affixed a GPS tracking device to a suspect's car without a proper warrant. It monitored the suspect's movements for several weeks, noting where his vehicle went and how long it stayed at each location.

While much of the data was ultimately excluded as inadmissible in court, after a mistrial the suspect was convicted of conspiring to distribute cocaine.

His lawyer subsequently argued that use of the GPS device violated his Fourth Amendment protections against unreasonable search and seizure.

But, Deputy Solicitor General Michael R. Dreeben, who argued the case for the government, said movements along public roadways have no guarantee of privacy, and police could have obtained the same information by having a team of officers follow the suspect.

As technology advances, it provides law enforcement agencies the opportunity to operate more efficiently.

"In an era of scarce resources it allows law enforcement to do more with less," attorney Todd Hinnen, a partner at Perkins Coie Law Firm, who was not involved in the case, noted to Fox News.

But critics, including the America Civil Liberties Union, warn that the government's warrantless surveillance power must be carefully limited.

In its brief filed in the case, the ACLU wrote, "Without judicial oversight, the police could track unlimited numbers of people for days, weeks, or months at a time. Americans could never be confident that they were free from round-the-clock surveillance of their activities."

During Tuesday's arguments, most of the justices seemed to have similar concerns.

"If you win this case then there is nothing to prevent the police or the government from monitoring 24 hours a day the public movement of every citizen of the United States," Justice Stephen Breyer told the government lawyer. "You suddenly produce what sounds like 1984."

That wasn't the only time George Orwell's chilling novel detailing a society marked by constant government surveillance was invoked during arguments.

Justice Sonia Sotomayor noted the array of satellites now able to photograph much of Earth.

"I don't see that far in the future when those cameras are going to be able to show you the entire world and let you track somebody on the camera from place to place," she said.

But the justices also pressed Stephen Leckar, the attorney arguing the case, to explain why the GPS tracking device should be disallowed if it simply provided the same information that actual officers could have obtained manually.

"The police could have had round-the-clock surveillance on this individual for a whole month or for two months or for three months, and that would not have violated anything, would it?" asked Justice Antonin Scalia.

"No," Leckar replied.

That answer led Justice Samuel Alito to continue the line of questioning.

"What is the difference in terms of one's privacy whether you're followed by a police officer for 12 hours and you don't see the officer or whether you're monitored by GPS for 12 hours?" he asked.

Leckar seemed to struggle to come up with an answer that satisfied his skeptical questioners.

But he also inadvertently sparked one of the hearing's lighter moments. When asked to differentiate the use of GPS devices from London society, where cameras line nearly every intersection in the city, Lecker responded that the situation in London "is pretty scary."

Scalia was more than a little hesitant to accept that as a legal argument.

"Well, it must be unconstitutional if it's scary," Scalia said as the courtroom erupted into prolonged laughter. "I mean, what is it, the scary provision of what article?"

The court's opinion is due sometime before the end of the term in June 2012.