But why go to the trouble of hiding that they're left-handed?

"The killer is left-handed!"

Ethan dropped this bombshell, causing Lucas to pause for a moment before he quickly leaned in to look at the screen, his face a mix of shock and confusion. "Hold up, Ethan. How can you tell the killer is left-handed just from that?"

"And about the cooked body's muscle texture and the cuts, isn't that kind of random? Can you really use that as a clue?"

Clearly, Ethan had made his judgment based on the cuts and texture of the victim's body, which was way beyond Lucas's understanding.

In criminal investigations, it's common to deduce the weapon and direction of attack from a victim's wounds. But this case at Gotham University, where the body was cooked before being chopped up, was something else entirely.

Lucas had never seen anything like it...

To determine the killer's dominant hand from the muscle texture and cuts under these circumstances was unheard of!

Seeing Lucas's astonished face, Ethan wasn't surprised at all,he had anticipated this reaction.

Using the cooked body's muscle texture for clues was beyond the scope of a regular detective's skills. In real-life investigations, figuring out a killer's dominant hand is incredibly tough, almost impossible. Killers act naturally, using whatever hand is most convenient to achieve their goal.

Even if a killer is left-handed, they might grab a weapon with their right hand if it's closer, especially under the adrenaline rush during an attack. With so many variables, it's extremely hard to determine the dominant hand.

It's not like in the TV shows where a quick glance at a wound can reveal which hand was used. That's just not realistic.

If Ethan hadn't experimented with various methods of murder in his attempts to commit the perfect crime, he probably wouldn't have noticed such details, let alone be so confident about them...

"The killer is left-handed."

At that moment, Ethan put up two different photos of the victim's body on the screen.

"Lucas, I know it sounds unbelievable to get clues from muscle texture and cuts, but let me explain a bit, and you'll see why I came to this conclusion."

Without any hesitation, Ethan pointed to the photo on top, the first bag of body parts found, which was almost mistaken for cooked beef and nearly eaten by a sanitation worker.

"Take a good look, Lucas. The muscle texture in this photo is clearly deeper on the right and shallower on the left, and the cuts are cleaner on the right side too."

"Imagine a big chunk of meat on a cutting board. Normally, when you start cutting, you apply more force because you're not worried about hitting the board. But as you get to the end, you subconsciously ease off to avoid making too much noise."

"That's a natural or subconscious behavior for anyone, and if you're a killer, you'd be even more conscious of the noise."

"This way of applying and relieving force would make the area where more force is applied have clearer and more distinct muscle texture and cuts."

"When a killer dismembers a victim, they're even more careful than we are when cutting meat, which definitely causes this uneven application of force."

"Now, looking at the body parts in the photo..."

"The right side's muscle texture and cuts are clearly more defined. According to the normal posture of cutting meat, it's undoubtedly with the right hand holding the knife."

"This information means..."

"When cutting the victim's body, the killer was using their right hand."

This detailed explanation left Lucas secretly stunned. He mimicked holding a knife with his right hand, feeling the change in force as he pretended to cut downwards.

Just as Ethan had said.

Once you feel like you're about to touch the cutting board, you subconsciously reduce your force, a human inertia that's hard to overcome!!!

After confirming this clue, Lucas clenched his jaw tightly and set down his coffee, his brow furrowing even more. "Ethan, this method of using muscle texture and cuts to determine the dominant hand..."

"I'm about 90% on board with it."

"But it feels like the application of this forensic technique is pretty narrow. After all, not many suspects are like the Gotham University butcher, coolly cooking and meticulously dismembering bodies. Most are probably too rushed even to dump the body properly, but here we can actually determine the dominant hand."

"However."

"It's weird, based on this detail..."

"The killer's dominant hand should be the right, not the left. How did you come up with the left-handed clue, Ethan?"

Although the application of this forensic technique was narrow, it now yielded tangible results from those twenty-year-old photos of the body—key clues!!!

Lucas had to admit, Ethan's knack for solving cases was frighteningly impressive.

Being a detective for so many years, he had never thought...

That you could determine someone's dominant hand from the different force used in cutting meat.

But he was growing more puzzled.

Clearly, from the body parts, you could tell the dominant hand was the right, so why was Ethan so sure the killer was left-handed?

Ethan didn't leave Lucas puzzled for long.

He pointed to the lower photo of the victim's cooked head, shown from multiple angles, gruesomely enough to give anyone nightmares.

"Lucas, take a close look at the cut on the neck."

"Using the technique we discussed earlier for determining the direction of the cuts on the body parts, you should be able to clearly see..."

"On both sides of the neck vertebrae, one side has a more pronounced muscle texture, while the other side is somewhat blurred and not as clear."

"But it's different from the direction of those other body parts."

"On this neck, the muscle texture on the left is more pronounced, while the right side shows where the killer clearly reduced their force."

"From here, we can conclude that the killer held the knife in their left hand when dismembering the victim's body and head, presenting us with two completely different answers."

"For dismembering the body parts, the killer used their right hand, but for the head, they switched to the left."

"It seems hard to distinguish, but actually, you just need to think about it a bit."

"Since dismembering the body parts involves pure muscle, the killer doesn't need to exert much force, but when cutting through the head, because of the spine..."

"The killer had to exert much more force!!!"

At this point.

Lucas didn't need Ethan to continue explaining.

He suddenly slapped his thigh, an epiphany lighting up his face excitedly: "When chopping through hard material or lifting heavy objects."

"Everyone subconsciously uses their dominant hand to exert more force, it's unavoidable."

"So, comparing the two tasks of cutting body parts and chopping through neck bones, we can clearly conclude..."

"The killer is left-handed, so they used their left hand to chop through the bone."

"The reason they used their right hand to cut the body parts was actually a deliberate disguise to confuse the police and throw off suspicion!"

"But why go to the trouble of hiding their left-handedness?"

"Though left-handers are less common among the general population, it shouldn't be necessary to hide it unless..."

Pausing for a beat, Lucas looked at Ethan, his eyes gleaming with insight.

"Unless..."

"The killer's profession is somewhat unique, and combined with being left-handed, it would be easy to single them out!!!"