The US Supreme Court agreed on Monday to decide whether police can attach a GPS tracking device to a suspect's vehicle without obtaining a search warrant.
The Obama administration is seeking to have the top US court overturn the ruling of a US appeals court in Washington which threw out the conviction in August of a Washington nightclub owner arrested for drug dealing.
The US Court of Appeals overturned the 2008 conviction of Antoine Jones, saying police violated his constitutional rights by tracking his movements with a satellite navigation system device affixed to his vehicle without a warrant.
The three-judge panel said the use of GPS, or Global Positioning System tracking, was a violation of Jones' constitutional guarantee in the Fourth Amendment against unreasonable search and seizure.
Urging the Supreme Court to take the case, the government said "a person traveling on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another."
It said this remained the case "even if 'scientific enhancements' allow police to observe this public information more efficiently."
"Prompt resolution of this conflict is critically important to law enforcement efforts throughout the United States," it said.
"The court of appeals' decision seriously impedes the government's use of GPS devices at the beginning stages of an investigation when officers are gathering evidence to establish probable cause," it added.
The American Civil Liberties Union said the case has significant privacy implications.
"The court has the opportunity in this case to safeguard Fourth Amendment privacy protections in the face of technological advances," it said. "Police surveillance using GPS technology raises significant privacy concerns."
"Sensitive information about who we are and where we go should not be available to any police officer simply because he is curious about someone," the ACLU said. "It must be subject to the judicial oversight that has always been a foundation of liberty in America.
"The court's decision in Jones could have a significant impact on everyone's privacy because most of us are carrying a tracking device everyday: our cellphone," it said.
© 2011 AFP