LAS VEGAS (AP) - Nevada police have tracked the movements of people through their cellphones, sometimes without obtaining proper court approval, according to court records and public documents obtained by the American Civil Liberties Union of Nevada.
A judge last year ruled North Las Vegas police improperly obtained the location of a murder suspect from his cellphone carrier but allowed evidence gathered from the illegal tracking to be used in court, citing in part the absence of a state law regulating such tracking, the Las Vegas Sun reported.
The Reno Police Department admitted in an internal document that cellphone tracking had been "misused" to locate stolen phones.
"Some cell carriers have been complying with such requests, but they cannot be expected to continue to do so as it is outside the scope of the law," the document said. "Continued misuse by law enforcement agencies will undoubtedly backfire."
Such actions on the part of law enforcement, first reported April 1 by The New York Times, have raised concerns among civil liberty advocates and some Nevada lawmakers.
A deputy Clark County public defender, Dan Silverstein, called cellphone tracking without a court warrant a key civil liberty issue and constitutional concern.
Silverstein is past president of Nevada Attorneys for Criminal Justice, a defense lawyers' group that has asked judges about cellphone tracking without warrants.
Silverstein said police in North Las Vegas and Las Vegas routinely use cellphone records to track people involved in investigations.
"It has become almost standard in the cases I see," Silverstein said. "Sometimes they obtain a warrant; sometimes they don't."
Las Vegas police and the Clark County district attorney's office did not respond to a request for comment.
Las Vegas police tell the ACLU that investigators sought 800 cellphone records over four years from mid-2007 to mid-2011. It wasn't clear whether those requests were for call logs or for cellphone location.
Police said they make requests to track cellphones based on a probable cause standard, and that departmental policy calls for "legal compliance to existing state and federal laws."
The Fourth Amendment of the U.S. Constitution prohibits unreasonable searches by government. To obtain a search warrant, authorities have been required to show a judge enough evidence to establish probable cause.
But Silverstein said in requesting cellphone locations and records, law enforcement sometimes uses a lower "relevance" standard.
Rebecca Gasca, ACLU legislative and policy director, said several Nevada lawmakers viewed the practice as "problematic."
Assemblyman Tick Segerblom, D-Las Vegas, said he believes law enforcement should have a search warrant before it accesses cellphone records.
The New York Times, using 5,500 pages of law enforcement documents obtained by ACLU affiliates, reported that law enforcement agencies across the country are using cellphone tracking as part of criminal investigations, but many have tried to keep it secret, fearing a public and legal backlash.
Silverstein said he first noticed this issue in 2005, when, in discovery for a case he was working on, he noticed a record of his client's locations along with a log of calls he had made from a cellphone.
That is now the norm in cases, he said.
In 2011, Clark County District Court Judge Valerie Adair found a North Las Vegas police detective didn't provide justification for tracking a handyman later convicted of murder.
"The police were entitled to the call records pursuant to (federal law), but they were not entitled to the cell tower location records," the judge wrote. But, she said, federal law did not allow the cellphone evidence to be thrown out.
The U.S. Supreme Court ruled in January that a Global Positioning System device law enforcement placed on a drug suspect's car violated his Fourth Amendment rights against unreasonable searches.
That case did not directly address cellphones, though many now come equipped with GPS devices.
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