Taherah Ghassemi’s body might still be buried in the woods — and the men accused of abducting and killing her might still be free — if it weren’t for cellphones.
The increasingly computerized devices played a pivotal role in ending the five-week search for Ghassemi and her alleged killers, reflecting the increasing usefulness of smartphones to law enforcement as the devices become near necessities for Americans across the socioeconomic spectrum.
Ghassemi disappeared in early April, and detectives over the weekend arrested her ex-husband, Hamid Ghassemi, and three other men accused of accepting $10,000 from him to abduct, kill and bury his ex-wife. The killing occurred several weeks after the Ghassemis settled a decadelong divorce battle, which resulted in Taherah Ghassemi receiving more than $1 million and two homes from her estranged husband.
Specifically, cellphone records aided detectives several ways in the investigation into Taherah Ghassemi’s disappearance.
A phone call made to her ex-husband several hours after she was last heard from led investigators to the caller, 20-year-old Tyler Lee Ashpaugh, according to a Sheriff’s Office report.
And more than a month after the Baton Rouge woman disappeared, on Saturday, it was location data collected from Ashpaugh’s phone that finally led investigators to the remote woods where Taherah Ghassemi’s body was found wrapped in a comforter stolen from her home, the report says.
The East Baton Rouge Parish Sheriff’s Office declined to comment Tuesday on the importance of cellphone records in the investigation into Ghassemi’s disappearance. But statements made Monday by the Sheriff’s Office homicide commander, Capt. Todd Morris, coupled with an arrest report, indicated key developments came largely from information obtained from cellphones.
“That played a part in going to that location,” Morris said Monday when asked how detectives found Ghassemi’s body buried in the woods north of Pine Grove in a rural area of St. Helena Parish.
Peter L. Scharf, a policing expert and professor at the LSU Health Sciences Center’s Institute for Public Health and Justice, said the potential value of cellphones to law enforcement during many types of investigations cannot be overstated.
“Cellphones can be the mother lode for law enforcement,” Scharf said, noting how the proliferation of such information has alarmed privacy advocates. “The evidence can be used both to point to possible criminal activity and also to exclude subjects from an investigation, which happens most of the time.”
Experts in mobile computing forensics — as the field is called — said cellphones provide a wealth of information on a user’s whereabouts, varying greatly depending on the type of phone, how it’s being used and whether it’s turned on.
“If you get a cellphone, it’s a gold mine,” said Avinash Srinivasan, an associate professor of computer and information sciences at Temple University who has trained law enforcement officers in computing forensics. “It, in fact, has more information than you can imagine.”
Although there are ways to reduce the geo-footprint left either on a user’s device or elsewhere, such as on a phone company server, experts in mobile forensics said most people willingly submit to the information being collected. Without doing so, the devices often become much less useful.
Applications, such as Facebook or Google Maps, usually require users to fork over their location information. In exchange, users can, when it comes to navigation apps, figure out exactly where they are any time of day or night, or how to find the nearest restaurants, theaters or gas stations.
“All of that data is stored somewhere,” said Jonathan Rajewski, an assistant professor of digital forensics at Champlain College in Burlington, Vermont. “Either it’s on your phone, or on the cloud, or on a server somewhere.”
And when law enforcement officers believe such location information is crucial to an investigation, such as in the Ghassemi case, they draft search warrants to collect the information from wherever it’s being stored.
“This information could be pivotal in a case,” Rajewski said. “It could be the smoking gun.”
Still, he said, location data is limited in its effectiveness on its own. The data will only show the position of the phone, not necessarily the person who was carrying it, Rajewski noted.
“It’s just another piece of the puzzle,” he said. “If they were blindly relying on the phone, that wouldn’t be a good investigation.”
Depending on the device, a phone could be logging location notes in several ways at the same time. An app could be sending location data to a server while the device itself takes notes about its positioning for every text message it receives. And if a phone call is underway, cell towers could be “pinging” the device, telling phone companies where the device is located.
“They don’t give a location specific, but they give a location general,” Richard P. Mislan, a professor of computing security at Rochester Institute of Technology, said regarding the cell tower records. Depending on how many towers are being used — generally up to three in urban areas and as few as one in rural areas — those records alone could show the location of a device within about 300 feet, Mislan said.
Even more recently, the proliferation of Wi-Fi networks has allowed more location data to be recorded by smartphones. In some cases, the device doesn’t even have to connect to the wireless network — maybe it just attempts to — for the information to be stored somewhere, experts said.
Some positioning data may be stored forever on the device. Other data may only be available for a matter of days or months, the experts said.
“Even if you turn it off, turn it on, it will create different types of pings,” said Srinivasan, the Temple University professor.
For example, the device might note where it was when the phone was turned off, then make another note once it is turned back on. Even without recording location data while off, such information could prove useful to law enforcement, mobile forensics experts said, because most of the data is incredibly reliable.
“You have to be a super smart, sophisticated criminal to tamper it,” Srinivasan said.
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