insight concepts,  research

polygraph: one test to rule them all

Photo credits: Shutterstock and Wikimedia Commons.
The Green River Killer passed a polygraph and went on to kill at least twenty more women. Photo credits: Shutterstock and Wikimedia Commons.

Imagine — you’re the Sheriff. Someone in your jurisdiction is killing women, at a rate of three a month. Sure, they’re castoffs, prostitutes and runaways, but they’re human beings and someone misses them. You find two suspects. You hit them both with your ultimate solution — the lie detector test, also known as the polygraph. One passes. The other fails. What do you do?

Of course you do what any sane officer of the peace would do, you let the innocent go and you investigate the guilty. In your understanding, this is what the test differentiates. The only problem is, that’s not what it does. In fact, in your very unfortunate case, the suspect who failed turns out to be harmless and the one who passed went on to kill at least twenty more women: the Green River Killer killed upwards of a total of seventy-one women before finally being convicted and imprisoned for life in 2001.

And thus the problem. There simply is no fail-safe lie detector test. In the case of the GRK, the FBI later changed their protocols so Ridgway would have failed (uh-huh, a little after-the-fact-truth-adjustment, anyone?) — but if it wasn’t him, it would have been someone else.

Which brings me to the insight concept behind the story Polygraph:

What if you could tell — with 100% accuracy — that someone was lying?

Would that be the be-all end-all of law enforcement? Would you always get your man? At the very least, one would hope for fewer than seventy-one deaths before you stopped the asshole.

At any rate, thus was born the idea for a series. All of my protagonists have some kind of limited “super power.” By that, I mean, something clearly delimited that takes them a little beyond human experience, but not into the realm of deus ex machina with, say, super-strength (how strong? well, as strong as you need it to be) or spidey-sense (you can sense a flea sneaking up on you at a hundred yards but somehow you missed the bad guy with the fifty-foot metal limbs crashing down).

In the case of Inspector Lukas Richter, he started off as a “walking polygraph.” But one that actually works 100% of the time as opposed to, you know, hopefully-better-than-chance-but-probably-not.

So how does the polygraph work? Well, you can get a convenient kit to plug into your laptop if you want to try it at home. I love the name, too: the LX 5000 computerized polygraph. We’re getting really Orwellian here, which is super scary once you realize most law enforcement agencies (FBI, CIA, larger police departments) subject their employees to it once a year or more.

"Bergonic chair" by Otis Historical Archives National Museum of Health and Medicine - originally posted to Flickr as Reeve041476. Licensed under CC BY 2.0 via Wikimedia Commons.
Bergonic chair” by Otis Historical Archives National Museum of Health and Medicine – originally posted to Flickr as Reeve041476. Licensed under CC BY 2.0 via Wikimedia Commons.

Anyway, the way it works is you hook the person who’s taking the test up to the computer and several vital signs are monitored. The actual mix of vitals I’m sure is proprietary and probably varies depending on whose test you use, but it’s sure to include: blood pressure, heart rate, skin (galvanic) temperature, and sweat response. The idea is then that there are detectable differences in these vital signs between when a person is lying or telling the truth. Seems reasonable, right?

There are at least two big hairy balls of problems with the approach.

1. it requires human judgment

Of course we want human judgment in the mix. Can you imagine the alternative? That we send people up the creek based on a computer’s say-so? Well, regardless, for now anyway the human administrator is integral to the test. But then we have the opposite problem — in spades. Imagine the set-up. You’re a trained polygraph administrator. Usually, you’re called in to test some hapless employee. You go in figuring whoever-it-is is probably a “good guy,” unless you find pretty obvious reason otherwise. Or, I suppose, unless you’re having a bad day and want to blame it on someone. But anyway, you’re predisposed to find the employee innocent. Since they probably are the lion’s share of the time, no big deal. Unless they’re that unfortunate enemy of the state, like Aldrich Ames, Karl Koecher, or Ana Montes. Oops.

On the other hand, there’s those few exciting times you’re called in with an actual suspect. Between the drab walls, under the hanging light, there’s some schmuck, and he’s yours. The police wouldn’t have dragged him in and subjected him to a polygraph unless there’s a damn good reason, right? Look at those shifty eyes. And those fidgeting fingers. And, those dancing feet. Obviously guilty. Right?

Or, maybe not. Thus the problem. You’re deciding lives, here. Literally.

2. science? what science?

Science likes cold, hard, reproducible facts. The polygraph doesn’t provide. Let’s say we have a rule of thumb that faster heart rate means lying, slower more baseline heart rate means truth. Alright. So … maybe 99 beats-per-second (bps) is okay but 101 is not. Well, answering your question, the guy hit exactly 100. Now what do you do? Remember — it’s a live, breathing, thinking human being hooked up to the machine. What if the person just thought about their last sexy date for that few milliseconds of answering? Or, what if they’re so freaked out by the whole experience anything sets them off, even if you ask whether the sky is blue?

Ultimately, as the National Academy of Sciences says in its huge tome on the matter, there is no reliable way to distinguish guilt from, say, simple fear.

So what are we left with? Well, I’m a fiction author so I get to change reality.

Enter Richter, a man with implants. These implants show him the vitals plausibly involved in lying: heart rate, skin temperature. To get this to happen, basically Richter had to have augmented senses — all five. I won’t give away all the details (in fact, I won’t even worry too much about all the details because this talent is the “ghost” in the machine). His most obvious feature is his right eye. It’s bionic, and gives him a view “something like” an IR camera — but not really. The point is, assume he can see (hear, feel, etc.) whatever vitals he needs to in order to make a judgment about whether someone is lying or not.

Given that, so what?

The rest of the world works as usual. There’s no hidden surprises, no bad guys with eight bionic legs or super strength. So what changes?

For starters, consider whether we have the same problems as with the polygraph. Yes, in fact, we do. They take a bit different forms, though. (And I would say more interesting forms.)

Richter is human, he’s opinionated no matter how much he tries to use his background in forensic psychology to keep himself objective. He doesn’t know this, but I will make him right — yes, that liar really is a liar — but it doesn’t matter, because he doesn’t know he’s right, and can’t in fact know 100% that he’s right. (No one thoughtful can.) So, sometimes he second guesses himself. He has that potential to shoot himself in the foot. Because, he’s human. Or, at least, as close as I can get making everything about him up on the page.

Image credit: Shutterstock.
Image credit: Shutterstock. Modified by me under license.

As for the second problem, yes, the “science” behind his implants is shadowy and largely unknown, but that only contributes to the real problem, which is he’s not admissible in court. In other words, even with his weird eye and hyper-senses, it comes down to his word versus the other guy’s. So, knowing someone is lying is only the beginning. It might help know where to look, but it doesn’t help find what he’s ultimately looking for. So, he needs to be as canny and observant as any other detective, and his cases are just as intricate and confounding.

None of that is to say there aren’t things he can do — situationally — that his more mundane fictional counterparts can’t do. He can see perps through walls. He can tell if someone’s holding a gun under their clothes. He can see through masks. His gift has perks and downsides, as you’ll see, sometimes with humorous results.

I won’t give any more away, you’ll have to read the books, such as Polygraph or The Bloodless Mask, or the many more I’ll come out with. Hope you enjoyed this window into what I was thinking when I made Inspector Lukas Richter. Thanks for reading!

Cy Wyss

I am an author currently residing in the Indianapolis area. I write and review mysteries, thrillers, and science fiction. Sign up for my newsletter at right and get a free short story.

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