Friday, December 3, 2010

From Meredith -- Goofy Mistakes

What are the goofiest mistakes writers make in books & TV when they deal with forensics in their stories?

I will preface by saying that I have made goofy mistakes myself, and will probably continue to do so. In my first book I had a bullet traveling at 4000 ft/sec—still not sure where I got that from. I nearly had Lake Erie about four times deeper than it really is; lucky for me my brother caught that one before publication. In Evidence of Murder I said people would die if oxygen fell below 25%, to which an astute and polite reader pointed out that since it is 21% of our atmosphere now, we would all be dead. (I checked my source document—the author actually wrote 25% of normal. Big difference.)

So I do not criticize others’ mistakes. And since forensic labs and scientists can vary in the manner and order in which they do certain things, just because my lab does things a certain way doesn’t mean it’s the only way. Several years ago I read an excellent mystery set in Finland in which the detective got hungry at a crime scene, so he went in and helped himself to a sandwich and beer from the dead man’s refrigerator. I don’t know if that’s honestly how the police operate in that country (after all, it didn’t substantially affect the crime scene, which had already been processed) or if that’s simply how the author assumed the police would operate.

That said, what comes to mind is the great Jeffrey Deaver’s book, The Bone Collector, and it wasn’t a mistake, exactly—he simply commented that no one has ever figured out how to get a fingerprint off a human hair. True, but why would you want to? A hair is so thin that any print obtained would not have sufficient detail to be useful.

Also, there is a scene where Lincoln asks Amelia to saw off the victim’s hands in order to leave the handcuffs unmolested. I’m sure I’m not the only CSI who wrote to point out that while the crime scene belongs to the cops, the body belongs to the M.E. The cops can’t even move it, much less remove parts. Besides, sawing appendages from an unfrozen body is a whole lot harder than it sounds.

Not to mention messier.

Lisa Black is a full time latent print examiner/CSI and the NYT bestselling author of the Theresa MacLean series, including Takeover, Evidence of Murder and the recently released Trail of Blood. Please visit her website at


Rebecca Cantrell said...

Loved the picture you chose to go next to the "sawing off handcuffs" bit. Very macabre!

We all make mistakes, and if we're lucky, they get found before publication. If it makes you feel better, I had Hannah use the word "yard" instead of the word "meter" once in A TRACE OF SMOKE. Grrrr....

A fingerprint from a hair? That must be one tiny finger. Still, someone has to catch the murdering fairies.

Rochelle Staab said...

Fascinating commentary. I loved your post!

Shane Gericke said...

"In my first book I had a bullet traveling at 4000 ft/sec...'

Almost the speed of a rejection letter :-)

Miss you guys ...

Meredith Cole said...

Thanks for answering my question, Lisa! Those were some pretty funny mistakes... I doubt you could eat from a dead man's refrigerator, no matter what the country. What if there was evidence in the fridge?

Kelli Stanley said...

Fabulous as always, Lisa--and the refrigerator bit reminded me of the Alfred Hitchcock episode in which the housewife serves up the murder weapon to the local cop ... ;)