“And they kept their phones off at all other times.”
“Interesting,” says Jane. “Didn’t know that.”
“No way you would until you look at the historical CSLI. But you’ll see that their phones aren’t sending any signals except at those times. So that right there—those synced-up times, turning off the phone otherwise—these are obviously the classic signs of two married people having an affair. Who really didn’t want their spouses to know.”
“We know Lauren was married, Dee. But we don’t know about the man.”
“Fair enough,” says Meadows. “Well, here’s another thing. Every one of Lauren’s communications took place at her home. I mean, down to the last one. And the other phone? The offender’s burner? Other than Halloween night, which was different—”
“Right, Halloween is different.”
“But putting aside the night of Halloween, it sure seems like the guy was texting from the same location every morning and the same location every night. Both locations were in Chicago. So let’s get into that.” Meadows starts to work her laptop. “You guys understand, I assume, that CSLI isn’t an exact science down to the microscopic point. You get that?”
“Yeah, you get a range from the cell tower. You get an area. The more cell towers around there, the smaller the area per cell tower.”
“Right, if you’re out somewhere rural, historical CSLI isn’t always your friend. But this guy was in the city, with a lot of towers, so it’s a bit more precise. Okay, I told you all of Lauren’s texts came from her home. Or from a fairly small area that includes her house, more accurately.”
“Right,” says Jane. “She could have been inside her house or on the back patio or the driveway—”
“Hell, she could’ve been half a block from her house, at least, and she’d still be pinging the same cell tower out in Grace Village. But yeah, all of Lauren’s texts, every one of them, hit her local cell tower, so you don’t need to see that. What you wanna see is the guy’s phone. The offender’s phone.”
Agent Meadows kills the lights and returns to her laptop. An image pops up on the conference room’s white wall, showing an aerial map with hundreds of blue dots and several thick red circles.
“This is the area by the elevated train downtown, near Clark and Lake,” says Meadows. “For the ten a.m. text messages, and I mean every single one of them, the burner pinged one of two different cell sites. One is right at Clark and Lake, the other is a couple blocks south and east on Dearborn between Washington and Randolph. Now these are high-density areas.”
“Lots of large commercial buildings,” says Andy Tate.
“Well, hang on,” she says. “Each cell site has directional antennas that divide the area into sectors. So for the cell site at Clark and Lake, the southeast antenna was pinged. And for the one on Dearborn, the northwest antenna was pinged. So that gets us a fairly small cross-sectional area.”
“An area of large commercial buildings?”
“Actually, no,” says Meadows. “Look at the buildings that fall into these sectors. At the intersection here of Clark and Randolph, you have the Daley Center. County offices, right? Judges, prosecutors, law enforcement. Then you have the Thompson Center—state governmental employees. And the county building and city hall. Same idea—government employees.” Meadows looks at Jane. “That fit your profile of the unknown subject? Some government employee? You said you had a working theory that this guy had money.”
“Just a theory,” Jane says.
That’s what Conrad’s ex-wife Cassandra thought—Lauren was looking for a fat wallet to replace the one who was divorcing her.
“Okay, well, we have a bunch of government buildings, and we have a massive parking garage in this sector. You think your guy was texting from a parking garage at ten in the morning?”
“Presumably not,” Jane says. “The assumption is he was at work. Just an assumption.”
“But a good one,” says Meadows. “So if someone with a lot of dough is at work, and he’s within this sector, he’s probably working in this building right here.” She taps a building on the corner of Randolph and Clark. “Forty, fifty floors tall. Lots of commercial companies, lenders, lawyers, the white-collar private-sector type. People with some money in their pocket.”
Jane looks at the map. “The Grant Thornton Tower.”