Forensics expert explains technology used to catch I-40 shooting suspect

RALEIGH, N.C. (WTVD) -- Following the Raleigh Police Department's press conference earlier this week regarding the week-long rush hour shootings along and near I40, officers worked hard to find and arrest the alleged suspect 23-year-old Andrew Graney.

Patrick Siewert has 15 years of law enforcement experience and is now a mobile forensics expert for Archer Hall. He commends the work of RPD.

"It sounds very similar to the D.C. sniper shooting. I would say that the hopping on it from a public safety perspective, seemed pretty good to me. I mean, when you don't have anything to go on, it's very hard to wrap your hands around it. Pretty good police work," said Siewert.

ABC11 obtained the search warrants in which it describes the two reports of a single shot being fired into homes around Centennial Ridge Way and Shire Lane.

A grey Hyundai Sonata was seen on surveillance video in the area of the calls around the same time. That information was used to gather and analyze cellphone tower data where shootings occurred. The registered owner of the Hyundai was pinned in the area of five of the listings, giving the officers a lead.

RELATED: NC State student accused of 12 'senseless and random' shootings on or near I-40 in Raleigh

"Everybody's cell phone is connected at all times, unless you put it in airplane mode or something like that, it's always connected to a cell tower. So the reason for that is the cellular network has to be able to find you, send you a call or text. It has to be able to find you. And so those passive connections are always present and that information is logged by the cellular provider," said Siewert.

He said cell phone providers host the information for a certain period of time, and a 'tower dump' can be acquired through a search warrant or emergency request. Law enforcement can also use information from vehicles that are connected.

"I don't like going off a single source of information. If I can get something to corroborate that, that would be great," said Siewert.

Law enforcement used the same patterns and clues to keep Wake County safe and arrested Graney at his home on Thursday afternoon.

Graney is being held without bond in Wake County Jail.

ALSO SEE: Timeline of dozen Raleigh shooting incidents on or near I-40 this week

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