The NYPD does not have a written policy on using the surveillance. Reuters

NewYorkCity'spolicehavemade extensive use of covert devices to trackcellphoneswithout obtaining warrants since 2008, a civil liberties group said on Thursday, revealing how frequently law enforcement in the largest U.S. city has employed the technology.


TheNewYorkCivil Liberties Union released files that showed theNewYorkPoliceDepartment used "cellsite simulators" to track nearbycellphonesmore than a 1,000 times over the past eight years.


The American Civil Liberties Union has identified 60 local, state and federal agencies thathaveadopted the devices in recent years, but the group has said there are likely far more. The extent of the devices has largely been shrouded in secrecy, as departments and private manufacturers such as Harris Corphaverefused to disclose information about their use.


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The documents released on Thursday were obtained by the NYCLU through a Freedom of Information Law request.


The NYPD does nothavea written policy on using the surveillance devices and does not obtain warrants when doing so, according to the NYCLU.

Instead, the department seeks "pen register" orders, whichhavebeen used for decades to gather information on specific phone numbers. The orders are issued by judges but require a lower standard than the probable cause needed for warrants.

The NYPD's practice is less stringent than the one adopted last year by the U.S. Department of Justice, which calls for warrants except in emergency situations.

"We stillhaveconcerns that this military equipment is being used in a civilian context," said Mariko Hirose, an NYCLU attorney. "At the very least, they should be using warrants and with a strict privacy policy that is written."

The devices mimiccelltowers and intercept signals from nearbyphonesto gather information. That data can include locations of calls, numbers that are called or texted and even the content of communications, the NYCLU said.

The simulators can also sweep up information from nearby "bystander"phones.

J. Peter Donald, a NYPD spokesman, said the department "ensures wehaveestablished probable cause, consults with a district attorney, and applies for a court order" before using the devices.

He added that the NYPD does not capture the content of communications or any data from bystandercellphones.

"Perhaps the NYCLU should fact check their press release before issuing it," he said.

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U.S. Representative Jason Chaffetz of Utah, a Republican, has introduced a bill to require warrants for the use ofcellsite simulators.

NoNewYorkcourt has yet tackled the question of whether the warrantless use of such devices is constitutional, Hirose said.

She said the NYCLU couldhavedifficulty establishing the legal standing to bring such a challenge, which would probablyhaveto come from a criminal defendant specifically targeted by a simulator.

The documents indicate the simulators were used to investigate a wide range of crimes, including murder, rape and drug trafficking.