News Release

N.Y.: Police Need Warrant for GPS Surveillance; Civil Liberties, Religious Groups Applaud Decision

Washington, DC­ (May 12, 2009) -- Police must obtain a warrant, based upon probable cause to believe criminal activity is afoot, before secretly installing global positioning satellite (GPS) transmitters on private vehicles, New York’s highest court ruled today. The case, People v. Weaver, has profound implications for the privacy rights of individuals and organizations. The National Association of Criminal Defense Lawyers and a diverse group of civil liberties and religious organizations filed a friend-of-the-court brief in the case arguing that persons’ privacy interests in where they go, what they do, and who they meet deserve some measure of protection from government surveillance.

NACDL President John Wesley Hall, a search and seizure expert, said the court made the right decision.

State police placed a GPS tracking device on defendant Scott Weaver’s car in December 2005 and tracked his movement for 65 days. Weaver was ultimately charged and convicted of a K-Mart burglary during that period. The GPS evidence indicated his car crossed the store’s parking lot at a slow speed at 7:26 p.m. the same evening the store was burglarized.

“Today is a great day for liberty, at least in New York,” Hall said in a statement. “This decision proves that the constitution is alive and able to preserve freedom even as the technological capacity to snoop and surveil advances by almost-quantum leaps.”

Low-cost GPS devices can be secretly attached to a vehicle and almost pinpoint its exact location on public or private property, within a few feet or yards, and transmit that information to virtually any computer with an internet connection. The devices are useful for tracking a vehicle or person in real-time, but the data also can be permanently stored and subjected to pattern analysis, revealing not just a person’s whereabouts, but his habits, associations, who his friends are, where he shops, banks and goes to church, and a host of other information. The coalition argued that court supervision is necessary to protect persons’ federal and state constitutional rights to privacy and association.

GPS tracking is not a “mere enhancement” of a police officer’s eyes and shoe leather, the court noted. “The potential for a similar capture of information or ‘seeing’ by law enforcement would require, at a minimum, millions of additional police officers and cameras on every street lamp,” the court said.

The civil liberties groups argued in their brief that such unfettered surveillance is unconstitutional and ill-advised as a matter of public policy. Led by NACDL, the groups include the New York State Association of Criminal Defense Lawyers, the New York State Defenders Association, the Electronic Frontier Foundation (EFF), the American-Arab Anti-Discrimination Committee (ADC), the Sikh American Legal Defense and Education Fund, the Council on American-Islamic Relations (CAIR), and the Union for Reform Judaism. They strongly urged the court to condition GPS monitoring upon judicial issuance of a warrant.

The brief was written by Susan J. Walsh, a partner at Moskowitz, Book & Walsh, LLP in New York City, NACDL Executive Director Norman L. Reimer and NACDL Assistant Director of Public Affairs & Communications Ivan J. Dominguez.

Continue reading below

“By its nature, GPS is a valuable tool because it permits long-term, sustained surveillance. But its potential for abuse is staggering,” said Walsh, lead author of the groups’ brief. “To allow this kind of personal data collection without judicial oversight is an Orwellian nightmare. The minimal time required to obtain a warrant based on probable cause restores balance and cannot credibly be said to impede legitimate law enforcement objectives.”

The court agreed with the groups in strong language. “One need only consider what the police may learn, practically effortlessly, from planting a single device. The whole of a person’s progress through the world, into both public and private spatial spheres, can be charted and recorded over lengthy periods possibly limited only by the need to change the transmitting batteries. Disclosed in the data retrieved from the transmitting unit . . . will be trips the indisputably private nature of which takes little imagination to conjure: trips to the psychiatrist, the plastic surgeon, the abortion clinic, the AIDS treatment center, the strip club, the criminal defense attorney, the by-the-hour motel, the union meeting, the mosque, synagogue or church, the gay bar and on and on.”

The technology stores, “with breathtaking quality and quantity,” the court said, a detailed profile of a person’s associations – “political, religious, amicable and amorous” – and the pattern of our professional and personal lives.

NACDL Executive Director Norman Reimer, one of the brief’s authors, said “The majority saw clearly that unlimited, uninterrupted 24/7 monitoring of an individual’s whereabouts is as much a First Amendment issue as it is a Fourth Amendment issue.” He pointed out that “the government can learn where a person worships, what clubs they attend, what political parties they participate in, where they sleep, and other personal and private information completely irrelevant to legitimate law enforcement needs.”

Continue reading below

Featured Products

The brief is available on NACDL’s Web site at:$FILE/gps.pdf

The court’s opinion is posted on its Web site at:


NACDL Communications Department

The National Association of Criminal Defense Lawyers is the preeminent organization advancing the mission of the criminal defense bar to ensure justice and due process for persons accused of crime or wrongdoing. A professional bar association founded in 1958, NACDL's many thousands of direct members in 28 countries – and 90 state, provincial and local affiliate organizations totaling up to 40,000 attorneys – include private criminal defense lawyers, public defenders, military defense counsel, law professors and judges committed to preserving fairness and promoting a rational and humane criminal legal system.