An account of the invention of the polygraph machine—or the lie detector, as it’s popularly known—in the early twentieth-century, and some of the first criminal cases that were associated with it.

In his author's note, Amit Katwala says that Tremors in the Blood is a book about science, psychology and people but that "this isn't a history book.” From context, it seems that what Katwala means by this is that he’s interested in narrative, drama, and human interest and not fuddy duddy history—apparently unaware that historical studies can give you all those things while also giving you the significance, the bigger picture of why you should care, what these events tell you about the time and place that shaped them. Katwala doesn’t really give you that here, which is one reason why this book doesn’t rise above common-or-garden “pop history”. The other is that it’s over-long and it isn’t well-structured/organised. Katwala does have a journalist’s eye for an interesting story, and some of the individual cases talked about here are engrossing, but the book as a whole didn’t fit together for me as well as I’d have liked. ( )

This work seems to be a very well researched and written piece. The narrative form is easy to read, not always easy to follow, but not sure it could be improved. The author does a good job of telling the story, bringing the characters to life and revealing a plot that is complex and interesting.
If you are interested in the history of crime and policing in the country or even if you are just a period who-dun-it fan you will find this story compelling and enthralling. ( )

Best for:
People who enjoy a mixture of history, true crime, and ethical discussions.

In a nutshell:
Author Katwala explores the creation and first two decades of the ‘lie detector’ (polygraph).

Worth quoting:
N/A

Why I chose it:
I like books like this usually - it feels like a subject Patrick Radden Keefe might have taken on.

What it left me feeling:
Educated.

Review:
In this book, author Katwala looks at the creator of the Polygraph, John Larson, who was a medical student interested in how one’s breath and blood pressure were impacted when someone knowingly told a lie. He eventually developed a machine that could allegedly detect these changes and tell when someone was telling a falsehood.

(He also used it as a very effective dating tool. The very first person Larson used it on in an official capacity was a sorority woman nine years his younger who he ended up marrying. I know people meet at work, but that seems to be a bit out of order.)

The book is told mainly through a couple of different cases from the 1920s and 1930s where it seems like the person is guilty, but the results of their polygraph tests are not conclusive. One is a man who might have paid people to kill his wife; another is a man who might have killed someone who was informing on him to the police. The stories themselves are interesting enough; bringing the polygraph into it makes them more complex.

In the US, polygraph results are not admissible at the federal level. But we have all seen Law & Order, right? People offering themselves up to take a lie detector test so that the police will stop investigating them. Or, conversely, we’ll see suspects refuse to take one, and people start to wonder why, and question their innocence.

The story follows as the polygraph gains popularity even though it cannot be used in federal cases. At one point Larson brings in someone named Keeler who takes over the work and sells it as much more infallible than it is, and seeks to make money off it, selling it to shopkeepers to test their employees to see if they’re stealing.

Here’s the thing though - the polygraph doesn’t really work. It definitely cannot definitively detect lies. And its use is ethically questionable at best. Larson sees this and speaks up; Keeler does not, though we get a sense with one of the later cases he’s involved in (one that ultimately results in someone being put to death) that he has his own doubts.

Overall this book was interesting and well-researched, but didn’t spend as much time as I would have liked on the ethics of the polygraph. The final coda was also deeply disturbing; it discusses how countries are making use of AI to detect lies. One claimed an 88% accuracy rate. Super! Unless you’re in the 12% and are telling the truth but the machine says you are lying.

As an aside: I listened to the audio version and I found the narrator’s pronunciation choices frustrating. I think part of it is the author is British so the narrator used some British pronunciations despite the narrator having a US or Canadian accent, which doesn’t quite work but I kind of get it. However, much of this book takes place in the San Francisco Bay Area, where I grew up, and the narrator consistently mispronounces the names of cities. That’s not hard to look up, so I’m confused as to how that got by the producers.

Recommend to a Friend / Keep / Donate it / Toss it:
Donate it ( )

I'm not a true crime aficionado, so I was somewhat put off reading this by the blurbs suggesting this book's appeal to true crime fans. Happily, the story, while engagingly written, does not delve deeply into gruesome details or even worry very much about who actually committed the crimes it explores. Rather, the focus of the story is on the development and exploitation of the technology of "lie detection" and how it came to gain such notoriety and influence. From Katwala's telling, polygraphs have been used from the very beginning almost as tie-breakers, when conflicting testimony and evidence leaves the truth unclear, but in fact the results only muddy the waters further, putting a pseudoscientific gloss on little more than educated guessing and intuition about an individual's psychology and physiology.

I was aware of the basic outline of the potential problems with polygraphs and other lie detectors, but the details of the story and some of the early influential cases were new to me. Similarly, I'd heard of August Vollmer as the "father of modern policing" but didn't know much about his specific innovations or processes. The book does a great job of introducing these topics and people, but the journalistic detail and immediacy of the narration make it a great read purely as entertainment.

I was mildly disappointed that the notes section didn't provide line-by-line citations for facts and quotes, but each chapter does have a listing of the sources used, which is pretty good for non-academic prose, so I felt reasonably confident that the facts were derived from primary or contemporary secondary sources, though for the sake of narrative interest, there are some assumptions made about characters' sensations or feelings. None of it feels overly manipulative, though, so I'd feel comfortable recommending this book as a popular historical introduction, as well as a compelling narrative.

This was a very interesting account of how the polygraph machine was invented - I had no idea it had been around since the 1920s. It read more like a novel than a non fiction book. I did feel like it was a little long and it jumped around at times. But overall I enjoyed it. ( )