“I also took into account the cause of death of family members for three generations.”
“OK, OK,” Dan said. “I hate to break up this celebration of killer inflictions, but I have a number.”
“You have a number?” Tobias asked.
“A phone number,” Dan answered, holding up the old napkin he had taken from Lindsay Richer's dresser drawer in the sorority house.
“Then I guess we will have to call it a tie. The reason I called earlierâand left a message with little Miss Death hereâis because at 4:17 this morning, I hit on the number that called your house. The call from the phone that doesn't exist. For those interested in accounting, the bill to locate the mystery number passed six figures this morning. I take cash or a cashier's check. Some of these phone companies are employing 516-bit encryption on their cell tower hard drives. It was not elementary. That is a lot of possible combinations to surf through.”
“Bit power,” Dan added looking at Sue.
Tobias picked up the conversation. “516 bit encryption equals possible combinations numbering in the millions of millions. Imagine a number with over fifty commas,” Tobias said. “A number so large there is no useful name for it, but it represents a lot of possibilities. It is represented by the number two, to the 516th power.”
“I get it,” Sue said.
“There are forty-seven towers within the Beltway. Split between the five major cell carriers and four lesser carriers. Each company had their own security and firewalls to bypass. I have been running crypto-breaking code non-stop since your last visit,” Tobias said.
“Then let's go upstairs and compare numbers,” Dan said.
Sue and Dan followed Tobias upstairs and through the doorway to the left. Sue gasped when she saw the array of computer equipment.
“I was secretly hoping for that reaction. I don't get too many visitors.”
“None that live to tell about it,” Dan added.
“Sit down on the sofa there. Give me the phone number you found.”
Dan handed the folded napkin to Tobias and the computer wizard held the worn paper between his pointer finger and thumb. “It has seen better days.”
“Haven't we all.”
Tobias shrugged his shoulders in agreement and sat down. He started typing on multiple keyboards and moved from monitor to monitor, pounding code at a feverish pace. He interjected intermittently and Dan was not sure if he should respond. “You know the Rolling Stones and U2 announced summer tours. I need to free up some resources so I can obtain the required number of tickets for re-sale.”
“I would love to see the Stones,” Sue added.
“Maybe we can go,” Tobias responded. “If I can find the time.”
Behind Tobias's back Dan scowled at Sue and shook his head.
“OK, let me show you what I found,” Tobias said. “I am running the query again so you can see the results as I did. And it does look like the number I found on the cell tower hard drives is the same as the one written here on the napkin.”
“So based on the napkin evidence, we can assume the mystery number was a cell phone that my nephew owned.”
“Yes. Well, we were running on the assumption it was the phone your sister-in-law called from on the night of her death. With the napkin evidence, we now know it was likely a phone your nephew possessed and that your sister-in-law merely used it on the night in question.”
“What can you tell me about the number?”
“On the screen, I have the detailed history of calls involving the mystery phone. We have one ping for that number in DC. Two in DC. Three in DC. One in Tysons. One in Alexandria. Two more in DC. Two more in DC. Another two in DC. Almost all the calls made on your nephew's phone are to an encrypted number which is represented on the screen by ten fives: 555-555-5555.”
“They use that number in movies.”
“Frequently. It is completely fictitious. The real phone number has been replaced with ten fives. Not the best news for us, but not a complete waste of time, either.”
Dan stared over Tobias's shoulder as data ran down the screen, too fast for him to decipher. He watched as the data scrolled and Tobias pointed out relevant information. A minute later the scrolling stopped and the cursor held its position on the bottom of the screen and blinked.
“Well, in total, your nephew's secret cell phone was only used a handful of times. We have sixteen calls in total. Thirteen of those calls were outgoing to the same encrypted number, represented by all fives. The sole incoming call to that phone was the last one made. It came from a cell tower near American University and terminated at a cell tower in Tysons. It was made two days ago. After your nephew was deceased.”
“That is the call that got Lindsay Richer killed.”
“Should I know her?”
“No. And it wasn't your fault.”
“All of the calls were found on Verizon towers, so Verizon is the carrier for your nephew's phone. The cell tower with the majority of the phone records is located on a building on Chesapeake Street, Northwest DC. The building leases a twenty-six-foot tower on the roof. If you look at the list of calls from this phone, there has been one call per month to 555-555-5555. Thirteen in total.”
“What else can you tell me about the calls to 555?”
“I have evidence a call was made, but the real number was manipulated and encrypted before it was stored on the cell tower's hard drive. I have a start and end time for the thirteen calls, so I can see that a phone call took place. In fact, except for the phone number itself, it appears the data for the calls is legitimate.”
“What about the call to my house?”
“Of the fifteen outgoing calls, we do indeed have one that was made from your nephew's mystery phone to your home number on the night your sister-in-law died.”
“At least I'm not crazy.”
“Hardly enough evidence to clear your mental state.”
“Did my sister-in-law call 911?”
“She did. Records indicate the call was terminated upon reaching the tower on Chesapeake Street.”
“Which did she call first?”
“911.”
“How much time between the time she called 911 and the time she called my house?”
“Two minutes.”
“What the hell was she doing for two minutes?”
“That I cannot answer. But based on these logs, she was not talking to 911. As I said, the call reached the cell tower and was terminated.”
“So, we have the phone number for my nephew's mysterious cell phone. It has fifteen outgoing calls, one to my home, one to 911, and thirteen to 555-555-5555.”
“Correct. Those thirteen calls to the number represented by all fives were very regular. One per month. Usually in the first week of the month. We can see that all of those calls were completely handled by the cell tower on Chesapeake Street. That cell tower never passed those calls to another tower, at least not to any cell tower in the greater metropolitan DC area.”
“So you can see when the number was called, the duration of the call, and whether or not the call was handed off to another cell tower in the DC area, but you cannot provide the number, beyond the ten fives.”
“That is correct.”
“Did you check to see if that 555 number is used elsewhere? Maybe there are calls from other phones outside of the beltway made to that same number.”
“At a thousand dollars an hour, I was sticking to the work you asked for. You wanted to know if I could find a missing phone call made to your house. I did. You didn't ask me about the numbers called by your nephew's mysterious cell phone or anything else further upstream.”
“Fair enough,” Dan said. “You know, the fact that most of the calls came through the same tower in Northwest DC is not surprising. That area was my nephew's backyard. That is where he went to school. Where he grew up. Where his mother lived.”
“You are missing the important part of the equation. The interesting tidbit of the logs is that the destination number of those callsâthe recipient of those callsâwas also within the same cell phone area. All of the thirteen calls started and ended within a very defined geographical area. Whoever answered the 555 number when your nephew called was close.”
“So, it's a landline?”
“No. The calls from your nephew's phone to that number were received by the cell tower but were not passed to a landline. It was very likely a fixed location cell number.”
“How does that work? Sue asked.
“Landlines are going the way of the dodo. Cell phones are the ubiquitous choice for communication. Fax machines can now employ cellular technology. You can control the systems in your home through your cell phone. Ditto for security alarms. So in looking at the 555 number, the only evidence I have of this number is in the Chesapeake tower location. If it is not a landline, it has to be a fixed location cell phone. Or a cell number that never ventures out of the footprint of the Chesapeake tower.”
Tobias waited for Dan to stop pacing.
Dan paused at the window and spoke over his shoulder. “Can you print out the metadata elements you do have for all the calls made on that phone, outgoing and incoming? And can you print the physical address of the cell tower on Chesapeake Street where the calls originated and terminated?”
Tobias tapped on the keys and a printer came to life in the far corner. Dan retrieved the paper and came back to Tobias's chair.
“What is the coverage area for that cell tower?”
“Give me a second.”
Sue was mesmerized as Tobias pulled up a map of DC and several dozen cell towers populated their respective locations throughout the city with overlapping concentric circles.
“The footprint of a cell-tower is not perfect,” Tobias added. “There are a lot of factors. Other buildings, elevation, capacity, height of the tower, technology components, weather. The size of the cell tower footprint can vary.”
Dan glanced at Sue who hadn't blinked. He watched as Tobias focused on the cell tower address and a bright red circle appeared, estimating the tower's coverage area. Tobias then overlaid the red circle onto a DC metropolitan map. He leaned back in his chair and smiled at his own work. “Thirteen of the calls were made to and received by a phone or location within that red circle.”
“What is the area, size-wise, more or less?”
“A mile and a half in diameter.”
“And we can't triangulate on a more defined location for a phone call?”
“No. We could triangulate a position if a cell phone was actively in use, or if the cell phone had its location services turned on. But without that, regardless of what you see in the movies, triangulating a phone call after the fact is impossible.”
“Probably won't matter anyway.”
“Maybe. I mean, if these guys are pros, they know how to cover their tracks.”
“And that may be good news.”
“Can you tell me how long it would take to check if anyone else called this 555 number, from any landline, from any carrier?”
“I can run a few tests to give you an idea of the cost. I'll start while you buy lunch.”
â
Lunch was comprised of a run to Tippy Tacos, a no-nonsense establishment at the end of a long-in-the-tooth strip mall near Merrifield. It was the first time Dan had ever been in public with Tobias and it would hopefully be the last. There is nothing like a backseat driver who sees death at every intersection, possible dismemberment with every passing car.
Back at his house, with a pound of rice & beans in his stomach, Tobias sat down in front of the computer and pulled up a blank screen.
“Houston, we have a problem.”
“Let me guess, there are no records of anyone else calling 555-555-5555.”
“Worse. It no longer exists.” Tobias cursed like a sailor in a port city bar and pulled a second keyboard from the far end of the table. He began typing code, one hand working each keyboard, his head on a swivel between monitors.
“These guys are indeed professionals.”
“Please tell me you are not going to say it is a good thing.”
“Nope. You still have the printout with the date and times of the calls from the tower in Chesapeake Street?”
“Yeah, why?”
“You are going to need it. All the records have been erased. All records on the cell tower. A hundred hours of work just vanished. All you have is the piece of paper.”
Dan pulled the paper from the pocket of his urban hiker pants and paced.
“OK. Let's see if we can use these guys' strength as their weakness.”
“What do you have in mind?” Tobias asked.
“Well, if you wanted to get rid of a cell phone, you would just get rid of it. Throw the phone away. Get rid of the fax machine. Change security systems. Destroy whatever is using the cell phone technology and the related number.”
“Sure. That would be the normal route for normal people.”
“Well, if you could just discard the phone, system, or machine using the cell phone, then why would these guys be racing to delete a record of a phone call, better yet, an encrypted phone call?”
“Because they are hiding something other than the phone number.”
“Exactly. I think I am done searching for something hidden. It's time to change tactics. Time to look for something I know doesn't exist.”
â
Dan stood by the car and waited until Sue sat in the passenger seat. He took a deep breath and checked the surroundings. He glanced up and waved at Tobias who was peeking out from behind the curtain on the second floor. Dan took a deep breath, exhaled slowly, and pulled the door handle.
“What do we do next?” Sue asked.
“There is no âwe.' Your work-study program is officially over. I'll sign whatever you need to show your university you completed your requirement. I'll give you full credit for whatever time you need. I'll sign your time sheets, and hell, I'll pay you for the rest of the school semester. Just let me know what you are reporting to the university and I'll support it.”