martes, 7 de julio de 2009

Growing Presence in the Courtroom: Cellphone Data as Witness

By ANNE BARNARD - Mikhail Mallayev, who was convicted in March of murdering an orthodontist whose wife wanted him killed during a bitter custody battle, stayed off his cellphone the morning of the shooting in Queens. But afterward, he chatted away, unaware that his phone was acting like a tracking device and would disprove his alibi — that he was not in New York the day of the killing. Darryl Littlejohn, a nightclub bouncer, made call after call on his cellphone as he drove from his home in Queens to a desolate Brooklyn street to dump the body of Imette St. Guillen, the graduate student he was convicted this month of murdering. The pivotal role that cellphone records played in these two prominent New York murder trials this year highlights the surge in law enforcement’s use of increasingly sophisticated cellular tracking techniques to keep tabs on suspects before they are arrested and build criminal cases against them by mapping their past movements. But cellphone tracking is raising concerns about civil liberties in a debate that pits public safety against privacy rights. Existing laws do not provide clear or uniform guidelines: Federal wiretap laws, outpaced by technological advances, do not explicitly cover the use of cellphone data to pinpoint a person’s location, and local court rulings vary widely across the country. In one case that unsettled cellphone companies, a sheriff in Alabama told a carrier he needed to track a cellphone in an emergency involving a child — she turned out to be his teenage daughter, who was late returning from a date. For more than a decade, investigators have been able to match an antenna tower with a cellphone signal to track a phone’s location to within a radius of about 200 yards in urban areas and up to 20 miles in rural areas. Now many more cellphones are equipped with global-positioning technology that makes it possible to pinpoint a user’s position with much greater precision, down to a few dozen yards. To determine where a suspect’s phone was in the past — as in the Mallayev and Littlejohn cases — investigators use company records that show a phone’s approximate location at the beginning and end of a call. To track suspects in real time, law enforcement officials must ask a phone company to “ping,” or send a signal to, a phone; for the effort to succeed, the phone must be turned on, though it does not have to be in use. The police can then use a vehicle with signal-tracking equipment to narrow down the location. The frequency and ease with which law enforcement agencies access cellphone data to track people is difficult to assess. Civil liberties groups recently obtained data from the Justice Department through a lawsuit showing that in some jurisdictions, including New Jersey and Florida, courts often allow federal prosecutors to track the location of cellphone users in real time without search warrants.

Investigators seeking warrants must provide a judge with probable cause that a crime has been committed. But investigators often obtain cell-tracking records under lower standards of judicial review — through subpoenas, which are granted routinely, or through an intermediate type of court order based on an argument that the information requested would be relevant to an investigation.

In what would be the highest-level court decision on the issue so far, a federal appeals court in Pennsylvania is expected to rule this summer on whether search warrants are required for the most basic cellphone tracking data — the electronic footprints that cellphone users leave behind in company records, often without realizing it.

In March, Google announced that it would require search warrants before releasing GPS data that pinpoints the movements of customers who use its mapping applications — like Latitude, which lets people see where their friends are — on their phones.

But phone and Internet companies want Congress to clarify the laws so that they are clear about their legal responsibilities.

Civil libertarians do not oppose using cellphone surveillance to solve crimes or save people in emergencies, but they worry that the legal gray area is enabling it to happen without much scrutiny or discussion.

“The cost of carrying a cellphone should not include the loss of one’s personal privacy,” said Catherine Crump, a lawyer for the American Civil Liberties Union, which filed a lawsuit along with the Electronic Frontier Foundation after the Justice Department did not respond to a Freedom of Information request for data. Federal and local law enforcement officials argue that people who obey the law have nothing to fear from cellphone tracking.

“Law enforcement has a responsibility to keep pace with the latest advances in technology in order to improve its efficiency in combating crime,” said Richard A. Brown, the Queens district attorney, whose office successfully prosecuted Mr. Mallayev, adding that criminals are “unknowingly Twittering with law enforcement” whenever they use their cellphones.

The data obtained by the civil liberties union provides a rare glimpse into crime-fighting techniques that law enforcement agencies are reluctant to talk about. Since Sept. 12, 2001, federal prosecutors in New Jersey have gained access to cellphone tracking information without warrants in 98 investigations resulting in 83 prosecutions.

Investigators have used cellphone tracking in a variety of ways: in Michigan to trace a fugitive suspected of killing his wife to a wilderness park, and in Florida to seek a suspected serial killer eventually killed in a police shootout.

Joseph A. Pollini, who oversaw kidnapping investigations as lieutenant commander of the New York Police Department’s major case squad, said he used it routinely — in one dramatic case tracing a ransom call to a house in Flushing, Queens, where the victim was rescued and the kidnapper arrested.

Cellphone records quickly sharpened investigators’ focus on Mr. Littlejohn in the death of Ms. St. Guillen, whom he met in the bar where he worked as a bouncer. Records from Feb. 25, 2006, showed that he called friends several times between 7 and 8 p.m. as his cellphone signal bounced off antenna towers near his home in South Jamaica, Queens, and off towers along the Belt Parkway that straddled the little-trafficked stretch of Fountain Avenue where an anonymous caller reported finding Ms. St. Guillen’s body.

Records showed Mr. Mallayev’s cellphone moving south from New York to his home in Atlanta in the hours after the killing of Daniel Malakov, the Queens orthodontist whose wife was convicted of hiring Mr. Mallayev to kill him. Mr. Mallayev’s son’s cellphone was tracked sending signals half an hour before the shooting to the tower closest to where Mr. Malakov was killed.

The five largest wireless carriers receive hundreds of requests a month from law enforcement just for real-time tracking, said Albert Gidari Jr., a Seattle lawyer who handles legal issues involving cellphone tracking for several companies. Civil libertarians say users whose phones have GPS-based services are unwittingly creating records that could give the government easy access to their movements.

In the case being weighed in Pennsylvania, the Federal District Court in Pittsburgh ruled last year that a search warrant was required even for historical phone location records, which the government had requested to track a suspect in a drug case. The decision upheld a magistrate judge’s ruling that people have a reasonable expectation of privacy regarding their physical location. Most Americans, the ruling said, do not know that their cellphones create a record of their movements and “would be appalled” to learn that the government can access it without showing probable cause. The Justice Department has appealed the case to the United States Court of Appeals for the Third Circuit. The civil liberties union and the Electronic Frontier Foundation are supporting the lower court’s decision, and say laws are needed, as the foundation puts it, to “keep Big Brother out of your pocket.” Kareem Fahim contributed reporting.


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