Double Jeopardy (18 page)

There was a brief pause, a few clicks, then: “What’s that? I’m sorry, there must be some static on the line. Who is this again?”

Cavanaugh smiled. “Bless you.”

It sounded like Crescatelli was blowing into the receiver. “Damn these car phones. The reception is horrible. Who’s calling, please?”

“John, I need access to a central switchboard computer terminal with the records for the last forty-eight hours for all lines in the greater Dallas/Fort Worth area Like, for example, the one you’re probably sitting in front of. And I need to make calls without being traced.”

Crescatelli pounded the phone against something solid. “I can’t believe this crappy reception. It’s these new fiber-optic cables, you know. They don’t work worth beans. Look, whoever this is, I expect to be at my terminal until six o’clock tonight, but between twelve-thirty and one-thirty everyone else in the office goes to lunch, so I’ll be here all by my lonesome. If you can’t get a better connection, you might consider coming by in person.”

Cavanaugh nodded. “Maybe I will. Talk to you later, John.” She pushed the red button, disconnecting the line.

“Travis,” she asked, “how would you like to pay a visit to the inner bowels of Ma Bell?”

T
RAVIS STOOD IN THE
midst of row after row of electronic switching equipment and tried to act more comfortable than he really was. He didn’t think anyone would recognize him; he was certain he’d never been here before. Somehow, though, that didn’t make him feel a bit safer. He’d never been to Cavanaugh’s apartment before, either, but that didn’t prevent them from finding him.

He was hiding behind dark sunglasses and beneath the brim of Cavanaugh’s fairly ridiculous fishing hat. Sure, it shaded his face, but he wondered if it didn’t attract more attention than it deflected. And it clashed with his necktie.

John Crescatelli was a jumbo-sized man whose fingers skidded across his computer keyboard at a speed faster than the eye could follow. The terminal was connected by shiny metal cables to a series of metal boxes, each equipped with flashing lights, buttons, and LED displays. To Travis, the place looked like a set from
Star Trek,
but Cavanaugh assured him it was all standard-issue telecommunications equipment.

“As I mentioned on the phone,” Cavanaugh said, “I need to be able to make phone calls that cannot be traced.”

Crescatelli nodded, apparently nonplussed. “May I ask why?’

“No. And let me remind you that I am not here, I never was here, you’ve never talked to me, you don’t know who I am, and you wouldn’t help me if you did.”

“Roger.” He gazed at the ceiling. “Someday I must seek a cure for this dreadful habit of talking to myself. I guess it stems from the fact that I’m fundamentally a lonely person.”

Cavanaugh smirked. “We’ll stand behind this row of beeping gizmos, just in case someone wanders in early from lunch.”

Crescatelli continued to stare at the ceiling. “What was that sound? The wind? Man, they really need to do something about the drafts in here.” He shuffled the papers on his desk. “Maybe this would be a good time to start outlining my doctoral dissertation—just in case I ever decide to go to college. In order to make an untraceable call, you need to understand about tandems.”

Cavanaugh scribbled into her notepad. “Tandems. That rings a bell.”

“The tandem is the key to the whole Bell telephone switching system. Each tandem is a carrier line with relays capable of switching other tandems in any toll-switching office in North America, either one-to-one or by programming a roundabout route through other tandems. If you call from Dallas to Tulsa and the traffic is heavy on all the direct trunks between the two cities, the tandem automatically reroutes you through the next best route, say for instance, through a tandem down in Shreveport or Houston, then up to Denver, then Wichita, then back to Tulsa.”

“Thanks for the fascinating background info,” Cavanaugh muttered. “So how do you make the untraceable call?”

“When a tandem is not in use, it whistles.”

Travis blinked. “Whistles? Like Yankee Doodle Dandy?”

“Mental note,” Crescatelli said. “Remove all frivolous asides from dissertation before publication. Anyway, when a caller dials a long-distance number, he is immediately connected to a tandem. The tandem stops whistling and converts the number into multifrequency beep tones, then transmits the tones to the tandem in the area code the caller wishes to reach.”

“Yeah, yeah, yeah,” Cavanaugh said. “I’ve got the general idea. Get on to the good stuff.”

“You would think this system is utterly immune to interference—who could talk to a tandem? No one could—until someone invented the first blue box.” Crescatelli reached into his bottom desk drawer and withdrew a small blue metal shell case. “You see, Ma Bell got careless. She allowed some egghead on the East Coast to publish an article in a technical journal which, in passing, revealed the actual frequencies Bell uses to create those multifrequency tones. Who’d have thought anyone would notice? Well, one squid at MIT read that issue. And half a day later he’d created the first blue box.”

Crescatelli flipped open a panel on the box to reveal a numeric keypad similar to that found on a telephone receiver. “Of course, Bell subsequently had all issues of that journal yanked from every library in the country. But it was too late. The entire AT&T switching system operates on twelve electronically generated combinations of six master tones—those are the tones you hear sometimes after you dial a long-distance number. The tone for each number is a combination of two fixed tones played simultaneously to create a certain beat frequency. Once those frequencies became public knowledge, all a guy had to do was get a Casio keyboard and a tape deck and record the tones. Play back the recording into a phone receiver and presto!—you’ve made a long-distance phone call without touching the dial.”

Cavanaugh was writing frenetically. “So your tape recorder can now make a long-distance call, something I could’ve done with my fingers. So what?”

Crescatelli shook his head. “I suppose for certain doubting Thomases it will be necessary to explain every little step. Remember the tandem networks? The blue box is programmed with tones that emulate the inactive whistling of a tandem. When the blue-box operator wants to call from Dallas to Tulsa, he might start by calling a toll-free number in Ypsilanti. The tandem in Ypsilanti is seized and starts listening to the beep tones that tell it which number to ring. Meanwhile, a mark is made on the Dallas office accounting tape noting that a call from your number to the Ypsilanti toll-free number has been initiated. The blue-box operator then sends a tone that emulates the inactive whistling of the tandem. The tandem assumes the caller has hung up and stops ringing the toll-free number. As soon as the blue-box operator stops sending the signal, the Ypsilanti tandem assumes the trunk is again being used and listens for a new series of tones to tell it where to call. The blue-box operator beeps out another number, say to Poughkeepsie.”

“Why would anyone call Poughkeepsie?” Travis whispered. Cavanaugh swatted him.

“The tandem relays the call. The blue-box operator can go on like this indefinitely, whistling his way from one tandem to the next, till he decides to connect with his ultimate destination. When he does, he can talk as long as he wants—’cause it’s all going to be charged to the owner of that first toll-free number. More importantly, for the purpose of those on the lam, the call cannot be traced by normal methods, and even abnormal high-tech methods will require much longer than usual.”

“Why is that?”

“Say someone has a trace on the receiving phone; his trace won’t run back to the caller’s phone—he’ll go back to the last tandem in the chain—and then the one before that, and the one before that, and so on and so on. Slowly. Eventually he’ll get back to the caller’s phone, but I’d like to think most people would have the sense not to talk that long.”

Travis whispered to Cavanaugh, “Did you get all that? Or any of that?”

“Enough,” she said, nodding.

“As any fool can see,” Crescatelli continued, “this information could easily be put to nefarious purposes, especially by cheapskates who don’t want to give the phone company its due. Come to think of it, it would probably be irresponsible to write this dissertation. I think I’ll scrap the whole idea.” He sighed. “What the heck. I’ll probably never go to college anyway.”

Cavanaugh stepped out from behind the machinery and quietly slipped the blue box into her purse. “You’re a gem and a half, John, but you’ve only taken me halfway home. How can I trace a phone call made in the past—one that’s already been disconnected? And don’t tell me it can’t be done. I work for the federal prosecutor’s office. I know it can.”

“Then again,” Crescatelli reflected, still staring at the ceiling, “there might be some legitimate uses for the article I envision. After all, once you understand about tandems, there isn’t much you can’t do with the phone system. Every major city has a central accounting computer that maintains their phone records. Of course, this is done for billing purposes, not out of any desire to aid law enforcement officials, but it does come in handy when the police want to know everyone who’s called a particular line within a given time period.”

“How do we access the central computer?”

Crescatelli batted a finger against his lips. “How does one access the central computer? Well, if you have a modem, you do it just like you call anyone else. All you have to know is the number.”

“Then we need the number of the central accounting computer for Dallas,” Travis said.

“Fortunately,” Crescatelli said, “the number of the Dallas computer, now displayed on this terminal screen, is totally top secret. I shudder to think what might happen if an unscrupulous person got hold of it.”

Cavanaugh jotted down the number.

Crescatelli punched a few more numbers on his terminal. “While I’ve been sitting here musing I’ve managed to take the phone line connected by modem to this computer through eighteen tandems crisscrossing the United States. Not absolutely necessary, but it would be best if this inquiry were not easily traced back here, just in case someone should become suspicious. Of course, I’m just doing it to remind myself how it’s done. Anybody could call on this line now and it couldn’t be traced back for twenty years.”

Crescatelli stood, stretched, and yawned. “All this brain work is tiring. I’m going to get a Coke. Maybe a doughnut, too.” He pushed his chair back and sauntered toward the kitchen.

“A prince among men,” Cavanaugh whispered as she slid into his chair.

“No kidding,” Travis said. “You must’ve saved that guy’s life.”

She began punching keys on the terminal keyboard. “As a matter of fact, I did.”

“How?”

“Oh … it’s a long story.”

“So shorten it.”

“Before John went legit, which was before John was John, he was a phone phreak. That’s with a
ph.
”

“What’s a phone phreak?”

“A telephone hacker. Used blue boxes and other devices to help friends make freebie long-distance phone calls. Not exactly admirable, but hardly a crime against humanity. Despite the fact that he was married, had one baby and another on the way, the phone company decided to make an example of him. John went underground. I was assigned to find him. I didn’t.”

“You mean, you did, but you didn’t turn him in.”

“Whatever. John is basically a good man, and I didn’t think an entire family should be destroyed just because Daddy made a dumb mistake he’ll never repeat. I’ve always had a soft spot for underdogs.” She looked at Travis awkwardly, then returned her attention to the terminal. “Did you follow all that rigmarole about switching tandems?”

“Not by a long shot.”

“Then watch.” She keyed up the modem and punched in the number on the computer screen. After a few moments they heard a typically shrill recorded operator voice say: “You have reached the central accounting records for area code 214. If you wish to make an inquiry, press one. If you wish—”

Cavanaugh pressed one.

“Please dial the number you wish records displayed for at the sound of the tone.” After a short pause they heard a beeping noise. “What’s your phone number, Byrne?”

He told her. “Why?”

“Just wait and see.”

Almost immediately, the screen filled with a long list of dates and times, each numbered sequentially. Beside the time and date stamp was a numeric indication of the length of the call.

“Good Lord!” Travis exclaimed. “That’s every phone call I’ve received in the past week!”

“Right you are.”

“What an enormous invasion of privacy.”

“You’re wrong, if only because your
privacy
was an illusion. Big Brother has been watching all along. You just didn’t realize it. Anyway, did you answer any calls after Moroconi phoned you?”

“No. I haven’t been there.”

“Good. Then we just need to take down the number of the last completed call to your phone.” She punched the number up. Travis noted that the date and time corresponded to Moroconi’s call. Cavanaugh highlighted the entry, then pressed the return key.

“Please hold,” the computer said.

Cavanaugh withdrew the tape recorder from her purse and pushed the record button. A few seconds later they heard the seven beeps of a phone number, as if dialed on a Touch-Tone phone.

“Thank you,” the recorded voice said.

“Bingo!” Cavanaugh exclaimed. She disconnected the phone line. “We got it.”

“We got what?” Travis asked, mystified. “A bunch of beeps?”

“Boy, you’re not following this at all, are you? How did anyone so slow-witted ever beat me so many times in court?” She rewound the tape, lifted the receiver on the desktop phone console, and played the beeps back into the receiver. After a few clicking noises, they heard the line ring.

Cavanaugh grinned proudly. “Can I cook, or can I cook?”

Someone lifted the phone on the other end of the line. “Million Dollar Motel.” The voice had a foreign accent. “Can I help you?”

Cavanaugh’s eyebrows bounced up and down. “What room is Al Moroconi in?”