In Missy Bever's case LE brought in "Stingray"technology that acted as a cell tower to intercept all the pings in the area. They used it near the church where Missy died.
NYPD To Use Tracking Experts To Assist Bevers’ Murder Investigation
"Sources say they hope the killer,
dressed in police gear, had an active phone that sent signals to surrounding cell towers as he – or she – confronted Bevers with a hammer.
Those signals could then draw a blueprint leading back to the attacker’s identity, investigators told CBS11.
They said no one is better at doing that than the NYPD. They have been known to use sophisticated tracking devices called “Stingrays.” According to the American Civil Liberties Union, since 2008 the NYPD has used the technology in about 1000 cases.
The cell site simulators mimic cell towers.
“[A phone] will automatically connect to the Stingray without any control from the user. It mines data off the phone, very quickly,” said Pete Schulte, former police officer and criminal defense attorney."
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