“Changing the pitch without changing the speed.”
Hank nodded. “Correct. That’s where things get complicated.”
“How about skipping the complexities?”
“I’ll do my best,” Hank agreed, again looking disappointed. “But there are a few geeky principles you need to grasp to understand what comes next.”
“Go ahead,” I said, deciding to shut up and listen.
“Okay,” Hank continued, removing his glasses and pinching the bridge of his nose. “There are several ways to achieve our real-time goal of changing the pitch without changing the underlying speed. One is a technique that converts a sound stream into its Fourier transform spectrum. The resultant frequency values are then modified in some way, after which an inverse mathematical function is used to convert the altered spectrum back to audio.”
“You’re losing me, Hank.”
“Sorry, but bear with me. Another technique involves layering numerous audio samples, or ‘grains,’—each no more that around ten milliseconds or so. By time-compressing or time-expanding each ‘grain’ and dropping segments of them back into the original, live-microphone frequency, you have the basis of a real-time pitch shifter. There are other methods as well, some of them proprietary.”
“Are any of those techniques reversible?”
“Depends,” Hank hedged. “If you know the exact software, and the exact settings—maybe.”
“Maybe?”
“Along with the complexities I just mentioned, it’s also possible to add randomizing parameters,” Hank explained. “With them, for example, a man’s voice can be made to sound like to a woman’s, or a child’s, or a space monster’s. If you don’t know how that original modification was achieved, there’s no way to reverse it.
“Damn,” I said, beginning to lose hope.
“There is some good news,” Hank went on. “For one, it’s difficult to mask someone’s speech patterns. Most people have a distinctive way that words come out of their mouth—rhythm, inflection, repetition, and so on—which can help make identification possible. For another, each of the voice-masking algorithms I mentioned has its own earmarks—sampling rates, noise distribution, harmonic addition ratios, and so on.”
My attention picked up. “So it might be possible to determine what software was used?”
“It would be difficult, but possible,” Hank agreed. “There are hundreds of voice-changing systems out there, from inexpensive software packages with a dozen generic presets, to algorithms with almost unlimited capabilities. By the way, the music industry has been using pitch-altering ‘Auto-Tune’ software for years—cleaning up missed notes, as well as using it for effect in songs like Believe.”
I nodded, recalling Cher’s hit from the nineties. “But it’s possible?”
“Theoretically. Of course, you would need a sample of the altered voice to start with.”
“I’m working on that.”
“Well, if there’s anything I can do to help, don’t hesitate to ask.”
“Thanks, Hank. I might just do that.” Then, glancing at my watch, “In the meantime, I have to get to work.”
“There is one thing that’s puzzling,” Hank mused.
“What?”
“If your suspect wanted to send you a voice message without getting caught, why resort to using complicated software when there’s a much simpler method—one that’s completely untraceable?”
“And that is?”
“Why didn’t he just type out his message and use text-to-speech to send it?”
13
Squad Room
Deluca was already at work in the squad room when I arrived. So was Lieutenant Long. Deluca was sitting hunched at his second-floor desk, with Long peering over his shoulder. Both glanced up as I hit the top of the stairs.
I crossed the crowded room, heading for Deluca’s workstation. On my way over Deluca shot me a chin nod, then returned his attention to a file on his desktop. “Lab work on Sandy Stafford,” he explained when I arrived.
“And?” I asked.
“Blood and urine analysis showed the presence of Ketamine and GHB,” Long replied.
I knew that Ketamine and GHB were both commonly abused street drugs taken to achieve euphoria and increased sexual drive. Ketamine was a veterinarian anesthetic with hypnotic, stimulant, and hallucinogenic properties; GHB, or gamma hydroxybutyrate, was a depressant.
Both were often referred to as “date rape” drugs. I also knew that Ketamine and GHB both belonged to a dissociative class of hallucinogens capable of disconnecting communication between brain and body—producing a state in which one could be aware of what was happening but unable to move. Mixing the two drugs was particularly dangerous, rendering a user susceptible to blackouts and amnesia, even coma.
“So besides imprisoning his victims, he’s drugging them as well,” I noted.
“Right. Increased histamine in the ligature marks on Stafford’s wrists and ankles indicates they were made before the time of death,” Deluca continued. “Same with the vaginal injuries.”
“Anything else?”
Deluca nodded, checking his notebook. “A match came back on the tire tracks we found at the Botanical Garden. Bridgestone All-Season Duelers. P215/70R16. Made for SUVs and commercial utility vans. Could come in handy.”
“If we find the vehicle for comparison,” I agreed. I hesitated and then continued, informing them that Captain Snead’s daughter, Ella, had been kidnapped from UCLA on the same night that the body of our victim had been dumped in the garden. I watched as their amazement changed from shock to concern as they did the addition.
“This has to be horrible for Captain Snead and his family,” said Long. “How is he holding up?”
“Not well,” I answered, recalling the look of desolation in Snead’s eyes the previous evening.
“Damn,” Long said softly.
We all fell silent.
“Not a random abduction,” Deluca finally muttered.
“No, it’s not,” I agreed, again realizing it could just as easily have been Allison. “I’m not certain what it means, but the killer’s choice of victims was not a coincidence.”
Once more, we all fell silent.
“After Ingram’s meeting last night, it’s safe to assume that you two will be on this full-time,” Long sighed at last. “Let’s head back to my office and start reassigning pending investigations. Afterward we can figure out what to do on the UCLA case. Kane, you have any ideas on that?”
“A few,” I said, following Long to his office at the back of the squad room.
For the next hour, working at a table in Long’s office, the three of us reviewed our open West L.A. homicide cases, discussing ways to shift responsibility to other squad detectives, many of whom were already overloaded. Working from memory, I gave status evaluations and detailed breakdowns of all current investigations, along with scheduled court appearances and personnel allocations for the following weeks. Once we had established a tentative plan for our open-case reassignments, Deluca and I returned to the squad room to tie up administrative loose ends with John Banowski, another homicide detective.
Banowski, who would be shouldering a significant portion of my D-III oversight responsibilities while Deluca and I were off the regular duty roster, was a thick-necked individual with a wrestler’s going-to-fat-physique and a thinning, crew-cut hairstyle that probably hadn’t changed much since high school. As Deluca pulled over a chair from an adjacent desk, Banowski settled his bearlike body on the corner of my workstation. There, for the next forty minutes, we went over our outstanding cases, file by file.
When we finished, Banowski shook his head. “Lotta work for the rest of the squad to pick up while you and Deluca are sidelined on The Magpie investigation,” he sighed, levering his bulky frame from my desk.
“You can handle the added responsibility, John,” I said. “Plus it’ll look good in your personnel folder.”
“Whatever,” Banowski
grumbled, heading back to his own workstation. “Just bag that asshole so we can get back to normal around here.”
Until then, Deluca hadn’t queried me about last night’s meeting in Ingram’s office, and I hadn’t volunteered. I was happy being back at work, and I didn’t want to spoil things by revisiting the politics involved in the case—figuring they would come up soon enough. As it turned out, I didn’t have long to wait.
As if on cue, Captain Snead appeared at the top of the stairs.
“Damn, trouble just arrived,” said Deluca.
Spotting us across the room, Snead began threading his way back. “Kane, Deluca,” he said upon arriving.
“Captain Snead,” I replied. “What brings you down here?”
“You know damn well why I’m here,” said Snead. Then, glancing at Deluca, “Give us a minute, Detective.”
“Sure,” said Deluca, giving Snead a look of sympathy. Then, returning to his desk, he busied himself by aimlessly riffling through paperwork.
“Actually, I don’t know why you’re here,” I said once Deluca had departed. “Don’t you have a task force to run?”
“Despite what Chief Ingram told you last night, I’m here to straighten out any misconceptions you might have regarding not reporting to me on the investigation,” Snead informed me. “I need to know every move you make.”
“Not going to happen.”
“Damn it, Kane! You can’t—”
“I realize we’re talking about your daughter,” I interrupted. “And I can imagine how you must feel. I’m not saying we can’t work together, or that you won’t be in the loop. I’m just not taking orders from you. Too many cooks in the kitchen. If you have a problem with that, take it up with Ingram.”
At that, Snead seemed to deflate. “I just can’t bear to think about what he’s doing to her,” he said quietly.
“I know. Look, let’s talk this through and see how we can best use our resources,” I suggested.
Snead nodded, pulling over a chair from an empty workstation.
I signaled Deluca to return. After Paul had seated himself across from Snead, I continued, again addressing Snead. “Here’s how I see things. As I said last night, it’s no coincidence that you and I find ourselves in this together. Thanks to media coverage on the Infidel case, whoever took Ella knows our history. He kidnapped the daughter of an LAPD captain to get as much media attention as possible, and he abducted her from my patrol area to make certain I’d catch the case. His phone calls tell me he wants me in the forefront of the investigation—probably because he assumes you and I will wind up on opposite sides of the case.”
“You’re saying this is some kind of game for him?” said Deluca.
“Looks that way. The question is, can we use that?”
We all paused in thought.
Not coming up with anything, I pushed ahead. “Okay, Captain Snead, I agree with your not revealing Ella’s abduction, at least for the moment, but let’s keep that possibility in mind. For now, there are a few things we can do.”
“Like what?” asked Snead.
“For one, we just got the tox report back on Sandy Stafford. It showed the presence of Ketamine and GHB in her system. Both are considered date-rape drugs, like those used on the previous victims. We might try locating the source.”
“Most so-called recreational drugs are gang-distributed,” Deluca observed. “We could check Los Angeles clubs, bars, rave scenes—looking for anyone who’s recently bought both. We should make sure the feds are following up on that aspect in the previous murders, too.”
“Good idea,” said Snead. “I have contacts in the gang units. I’ll look into date-rape drug purchases around L.A. What else?”
I thought a moment. “How did he get my cellphone number? Or yours?”
“Someone in the department?” suggested Deluca. “Someone who knows you both?”
“That would be a fairly short list, but we should check,” I said. “We could also find out whether this mutt called anyone else during his previous murders. If that’s the case, our man may have hacked into his victims’ social media sites—Facebook, WhatsApp, Messenger, and any phone apps that are out there.”
“I have a Facebook account,” Snead noted doubtfully. “I don’t use any of those others.”
“No, but your daughter probably did,” Deluca pointed out. “And when she added her contacts to Messenger, for instance, your cellphone number may have been included. Messenger then matched your cell number or your email address to known Facebook users, and bingo, you’re in there—whether you are Facebook friends with any of those people or not.”
“Let’s ask the Bureau to have their nerds check on that,” I suggested. “The feds are already researching Sandy Stafford’s Facebook friend requests, along with comparing her social media sites to those of previous victims. Having them look into the possibility of a phone hack would dovetail in.” Then, moving on, I turned to Deluca. “How’s the UCLA canvass for witnesses going?”
Deluca shook his head. “We’re still searching for anyone who might have seen the killer entering the garden. Along those lines, I set up a meeting with UCPD to discuss campus security cameras,” he replied. “We’re supposed to get together this morning at UCLA with Lieutenant Greenly.”
“Good work, Paul,” I said. Then, to Snead, “Speaking of security cameras, we have a reasonably accurate timeframe on the murder. How about checking traffic cams in the area? If nothing else, we should have a shot of the killer leaving the site, no matter which direction he went. We’ll have footage of ten thousand other commuters as well, but we could compare our findings with traffic cam footage from the killer’s other dumpsites—maybe come up with a shot of the guy leaving another location.”
“And maybe even get a license number,” added Deluca.
“I’ll have my team look into that, too,” agreed Snead. “Anything else?”
“The killer used voice-changing software both times he called me,” I said.
“Same with me,” said Snead.
“If we can get a recording of his voice the next time he calls, we might be able to identify the masking software he’s using,” I suggested, deciding not to mention that I had already started looking into that. “You’re ready to record him if he calls again, right?”
Snead nodded. “I am, but so far he hasn’t actually said anything incriminating. You realize that with the exception of criminal activity, California requires two-party consent for voice recording, right? It could present a problem.”
I knew Snead was bringing up a “fruit of the poisonous tree” legal issue—an evidentiary doctrine stating that any illegally obtained evidence was inadmissible in court, as was everything else resulting from the original illegal search.
“That dirtbag will never see the inside of a courtroom,” Deluca predicted.
“You may be right, Paul,” I agreed. “But if we do get a recording of the killer’s voice, let’s be careful about how we submit it as evidence. Granted, there is no expectation of privacy for someone using the phone in the commission of a crime. Even so, given how careful this guy has been with what he’s said so far, both Captain Snead and I should get warrants on our cellphones to ensure there’s absolutely no room for a motion to suppress, if we get the case to court. Suspenders and a belt. You understand what I’m saying here?”
Snead and Deluca both nodded. “I’ll get it done it today,” said Snead.
“Okay,” I finished, making a mental note to do the same. Then, glancing at my watch, “Deluca, you and I need to get over to UCLA and talk with this Lieutenant Greenly.” Rising, I added, “Captain Snead, thanks for stopping by.”
Snead stood as well. As he did, I regarded him closely. He looked exhausted, almost shell-shocked, as if he hadn’t slept in days.
“One more thing, Captain.”
“Yes?”
“A lot of capable people are doing everything possible to locate your daughter,” I said quietly. “We’ll do our b
est to find her . . . no matter what.”
14
Getting Warmer
The UCLA police department is one of ten University of California patrol agencies—each with statewide jurisdiction over campuses and properties owned by the UC Regents, each with its own sworn officers and police chief.
I knew a number of LAPD officers who had gone to work for UCPD, so upon bulling my way through a crowd of reporters still clogging the Botanical Garden’s south entrance, I wasn’t surprised to find an old friend there waiting.
“Dan, it’s been too long,” said Tony Choi, a colleague who had recently retired from the Beverly Hills PD to take over as UCLA chief of police. “Glad to see you’re still upright,” he added, his round, tanned face splitting in a grin.
“Me, too,” I chuckled, shaking Tony’s hand. Tony was standing inside the yellow perimeter tape, accompanied by a uniformed UCPD officer. Nearby, an LAPD patrolman was still keeping the crime-scene log, as the garden grounds continued to remain sealed. I also noticed that across the street reporters were busy doing follow-up reports—probably enumerating all the things they didn’t know and hadn’t learned since yesterday.
“This is Scott Greenly,” Choi continued, indicating the intense, whip-thin man beside him. “Lieutenant Greenly heads up our Investigations Division. His detectives did the initial workup on the murder, so he should be able to answer any questions you may have.”
“Good to meet you, Greenly,” I said, shaking his hand. “My partner, Paul Deluca,” I added as Deluca, who had a court appearance later that afternoon and had driven over in his own car, ducked under the tape.
“Pleasure,” said Deluca, shaking hands with both Greenly and Choi. “Wish it were under different circumstances.”
Dead and Gone Page 89