What's the Difference Between a Killer's Signature and M.O.?

iStock/fergregory
iStock/fergregory

True crime shows, documentaries, and podcasts are everywhere these days, not to mention all the crime-focused movies and TV shows—like NBC's Law & Order: SVU, CBS's CSI: Crime Scene Investigation, and Netflix's Mindhunter. And you've probably heard terms like signature and M.O. being thrown around a lot without much explanation as to what they mean, or how they're different.

If you're confused about the difference between them, well, you’re not alone. As former FBI agent and behavioral analyst John Douglas notes in his book Mindhunter: Inside the FBI's Elite Serial Crime Unit (which the Netflix series is based on), "Both [signature and modus operandi] are extremely important concepts in criminal investigations analysis, and I have spent many hours on witness stands of courtrooms throughout the country trying to get judges and juries to understand the distinction between them."

Douglas, who was recently in New York to promote his new book, The Killer Across the Table: Unlocking the Secrets of Serial Killers and Predators with the FBI's Original Mindhunter, out now, helped break down the difference between signature and M.O. for us.

M.O. stands for Modus Operandi, and, according to Douglas, it's a learned, dynamic behavior. "When a criminal starts perpetrating crimes, if something doesn't go right, he's got to perfect the M.O.," he tells Mental Floss. "He's got to get it better and better." In other words, unless an offender executes the perfect crime his first time out, he'll continue to tweak his M.O. as he goes. The method of committing the crime is modified for success. That's why, Douglas says, "you shouldn't link cases together strictly by modus operandi. … You don't do that because those characteristics could fit people that have nothing to do with the case as well."

But what you can use to link crimes together is an offender's signature, a term that Douglas says he coined. "A signature is a ritual—something [that] is done that is not necessary to perpetrate that particular crime," he says. "The signature is the ritual that is unique to the offender, and that's what you're looking for."

To demonstrate what he means, Douglas uses sports as an example. "It's like a baseball batter [who], before a ball comes in, does rituals," like touching his hat or cleats. "Or shooting a basketball: bounce it three times, [do a certain move], take the shot. It's not necessary to get it in the hoop or hit the ball, but in his mind he's got to do it. He's got to do it this way."

In Mindhunter, Douglas acknowledges that "the differences between M.O. and signature can be subtle." To demonstrate just how subtle, he compares two robbery cases. Both robbers made their captive undress; one "posed them in sexual positions, and took photographs of them" while the other did not take photos.

The latter made his hostages undress "so the eyewitnesses would be so preoccupied and embarrassed that they wouldn't be looking at him and so couldn't make a positive ID later on," Douglas writes. That's an example of M.O. The former robber is an example of a signature, because it wasn't something the offender had to do to rob the bank—and actually put him at risk of being caught, because he was in the bank longer. "It was something he clearly felt a need to do," Douglas writes.

Because the signature is unique to the offender, Douglas says that you can use it in trials: "A case in Washington state, the subject was posing the victims after he killed [them]. And all that was allowed for me to testify to."

There's one challenge with signatures, though. "You can only see it when it starts showing up in repetitive crimes," Douglas says. "You can't look at a single case and say, 'Oh, this was the signature.' Say the victim is posed—that may end up being the signature, but you've got to compare it to something, later on."

As criminology professor Scott A. Bonn, Ph.D., points out in a post for Psychology Today, "While every crime has an M.O., not all crimes have a signature." Now, whether you're listening to a true crime podcast or watching an episode of Mindhunter, you'll know the difference.

Keep Your Cat Busy With a Board Game That Doubles as a Scratch Pad

Cheerble
Cheerble

No matter how much you love playing with your cat, waving a feather toy in front of its face can get monotonous after a while (for the both of you). To shake up playtime, the Cheerble three-in-one board game looks to provide your feline housemate with hours of hands-free entertainment.

Cheerble's board game, which is currently raising money on Kickstarter, is designed to keep even the most restless cats stimulated. The first component of the game is the electronic Cheerble ball, which rolls on its own when your cat touches it with their paw or nose—no remote control required. And on days when your cat is especially energetic, you can adjust the ball's settings to roll and bounce in a way that matches their stamina.

Cheerable cat toy on Kickstarter.
Cheerble

The Cheerble balls are meant to pair with the Cheerble game board, which consists of a box that has plenty of room for balls to roll around. The board is also covered on one side with a platform that has holes big enough for your cat to fit their paws through, so they can hunt the balls like a game of Whack-a-Mole. And if your cat ever loses interest in chasing the ball, the board also includes a built-in scratch pad and fluffy wand toy to slap around. A simplified version of the board game includes the scratch pad without the wand or hole maze, so you can tailor your purchase for your cat's interests.

Cheerble cat board game.
Cheerble

Since launching its campaign on Kickstarter on April 23, Cheerble has raised over $128,000, already blowing past its initial goal of $6416. You can back the Kickstarter today to claim a Cheerble product, with $32 getting you a ball and $58 getting you the board game. You can make your pledge here, with shipping estimated for July 2020.

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Why Did Noon Used to Mean 3 p.m.?

3 p.m. is basically noon for people who wake up at 12 p.m.
3 p.m. is basically noon for people who wake up at 12 p.m.
Mckyartstudio/iStock via Getty Images

If you’re a late sleeper, you might find yourself thinking 12 p.m. seems way too early to be considered midday, and the word noon would much better describe, say, 3 p.m. It turns out that ancient Romans would have agreed with you, if only for etymological reasons.

As Reader’s Digest explains, the days in ancient Rome were split into four periods of three hours each. The first hour was at sunrise around 6 a.m.—called prime, for first—followed by 9 a.m. (terce, denoting the third hour), 12 p.m. (sext, for sixth), and 3 p.m. (none, for ninth).

According to Merriam-Webster, Middle and Old English borrowed the time-keeping tradition, along with the Latin word for ninth, which was changed to nōn and eventually noon. Though we’re not sure exactly when or why noon started referring to 12 p.m. instead of 3 p.m., it could have something to do with Christian prayer traditions. In the Bible, Jesus’s crucifixion is said to have taken place at the ninth hour, and that’s when worshippers partook in their second of three daily prayers; the others were in the morning and evening. It’s possible that hungry monks were behind noon’s gradual shift from 3 p.m. to 12 p.m.—since their daily fast didn’t end until after the midday prayer, they had a built-in motive for moving it earlier.

While we didn’t exactly stay true to the original Latin meaning of noon, there’s another important remnant of ancient Rome hiding in the way we tell time today. Romans referred to 12 p.m. as meridiem, for midday, and so do we. A.M. is an abbreviation for ante meridiem, or before midday, and P.M. means post meridiem, or after midday.

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