The Murder That Never Was (Forensic Instincts 5)

“I’m clear on my role once we get to Chicago, but how is Otter supposed to tell us the necessary information about cell phone calls?”

“So glad you asked,” Ryan replied. “As you know, Shannon was able to provide me with Jim’s cell phone number. I checked. Jim used U.S. Cellular for cell phone service. I was able to grab the last month of cell phone records before their intrusion detection systems shut me down. From there, I found a few phone numbers of interest. Some of them were to other trainers in the area. Those guys generally had regular cell phones. Maybe they were friends, colleagues, or maybe they were drug dealers like Jim. That’s part of what your investigative skills will need to determine when we interview them. But one number in particular kept popping up—and with greater frequency right before Julie was murdered. I traced the number to a TracPhone. Nontechnical types and some senior citizens prefer TracPhones, but a disposable cell phone—a burner phone—is the communication tool of choice for criminals. Phones are purchased with cash and tossed when the minutes run out.”

“Boy Genius, I was with the FBI, remember? I know what a burner phone is a

nd how it’s purchased. In fact, I’m pretty sure everyone who watches TV crime shows knows that.”

“Sorry.” Ryan had the decency to look sheepish.

“Forget it. Let’s get back to your analysis. So Jim called his distributor’s TracPhone. How are we going to find out who this guy is?”

“Otter.”

Once again, Marc rolled his eyes. “So Otter is clairvoyant like your girlfriend?”

Ryan shot him an irritated look. “Careful with your choice of words. Claire and I are…well, Claire and I. No label’s been assigned to it.”

“Fine. Whatever. Go on.”

“Otter’s not psychic, just curious.” Ryan stopped talking to glance out the window, his attention temporarily focused elsewhere. “Before I give you more than you can absorb in one shot, I need an Egg McMuffin and a large cup of coffee. Pull off at the next exit. The golden arches I just saw made me hungry.”

“No health food today?”

“Not unless you know of a health food restaurant right off the highway with a drive-through window. I’ll have to make do.” A grin. “Plus, your body needs an Egg McMuffin every once in a while.”

“You don’t have to twist my arm. I’m starving. And I need some coffee, too.” Marc pulled into the right-hand lane, cruising until the exit ramp appeared and those familiar golden arches rose through the trees, beckoning hungry travelers.

They zipped through the drive-through, grabbing their food and getting right back on the road, this time with Ryan at the wheel. He was the king of eating, talking, and driving, all at the same time.

“To continue. Otter will navigate the digital rivers of Verizon’s Chicago network operations center, which TracPhone uses to handle its customers’ calls. He’ll find every cell tower that was ever involved in handling a call to or from that TracPhone number and send all the detailed information stealthily back to Yoda. Yoda will align the cell phone call information with cell tower log files using time stamps recorded down to microseconds.”

“So how is this going to tell us who Mr. Anonymous is?” Marc interrupted to ask.

Ryan raised a hand. “I’m getting to that part. Yoda will be able to triangulate a geographic ‘red zone’ from the cell tower data. You see, when a cell phone places a call, it contacts cell towers in the area. The idea is to use the one with the best signal strength. Usually, it’s the closest one to the subscriber. Sometimes it’s not, because of some natural or man-made obstacles—like a hill or a building that impacts the signal strength. By doing a ‘mashup’ of the cell tower locations—Google Earth for the terrain assessment and signal strength data on the TracPhone calls—Yoda should be able to narrow the location of the distributor to within a block or so.”

He took a belt of coffee. “People are creatures of habit. They place the bulk of their cell phone calls from home, their office, or their favorite Starbucks. When the same tower handles cell phone calls at the same time of day, that can give us a clue as to where this guy hangs out. For example, if Yoda comes up with a location during the day in a business district, then we can guess that the distributor has an office in the area. At night, especially late at night, he’s probably home. I suspect this guy will be doing business out of his car and his apartment.”

“Okay,” Marc said, processing all this information. “So we know that this scumbag lives within a block or two of some address. We can’t go door to door interviewing people. I don’t have my FBI credentials anymore, remember?”

“No worries on that score,” Ryan assured him. “We won’t have to. Once Yoda figures out the area we’re interested in, Otter will switch gears and head in the opposite direction. He’ll focus on calls made using the same geographic pattern of cell towers but from another cell phone. In my experience analyzing communications in criminal networks, bad guys will protect themselves from discovery by using a burner phone to talk to people on the street. In this case, that’s what the distributor did with Jim. So if Jim were arrested, the cops would only have a disposable cell phone number and no leads back to the distributor.”

“Dead end.”

“Yup. But a distributor has multiple business relationships and, at some point, would be talking to someone higher up in the food chain. That person wouldn’t want the hassle of dealing with revolving phone numbers for all his distributors. He might have thirty people he needs to talk to on a regular basis, spread out all over the US. Imagine the chaos. The person above the distributor would only accept phone calls from known phone numbers.”

“Got it.”

“So, in a long-winded way, we’ll use the burner phone to find a location. We’ll use that location to find a regular cell phone number that is being used by the same person. Then we’ll go on to use that info to find who the distributor called. My hope is that someone at the top is not concerned about cell phone anonymity, but if they are, we can track them to within another block or two radius. Otter will keep plying the digital rivers of cell phone data and, with Yoda’s help and computation resources, build a map of the criminal network using their communications to uncover the players.”

Marc snorted. “Between the government listening in to our cell phone conversations, surveillance cameras everywhere, people capturing conversations, pictures, and videos using smartphones, and tech prodigies like you designing, integrating, and hacking all this, there really is no place to hide any longer.”

“That’s right. If you’ve got any secrets I don’t know about, I will soon.”

Marc chuckled. “No such luck. You’ll have to play spy somewhere else. I’m as clean as a whistle—other than my work at FI, which is no secret to you. But it does sound like I underestimated Otter.”

“You did. But I don’t expect you to get my level of genius.”

“Just drive, Ryan,” Marc said and turned up the radio. “The sooner we get there, the better.”