Coroner Coroner

"It was obvious that someone attacked from behind, wrapped a rope around her neck twice, and strangled her hard."

Lin Xinyi said so, but his expression became a little more relaxed.

Mao Lilan looked over with some puzzlement:

"Mr. Lin, does this discovery have any special significance?"

"Of course." Lin Xin nodded:

"Using a rope to strangle someone is the easiest attack method to leave traces."

"First, it requires the killer and victim to be physically close together."

"Secondly, it takes a lot of time to strangle people to death and faint them."

"The victim is a living person, and it is impossible not to struggle and resist under the suffocating pain."

"In the process of resistance, because the two bodies were close together, the victim could easily grab important biological samples such as hair and dander from the murderer."

"At this time, carefully observe the victim's fingernails, maybe you will gain something."

As he spoke, Lin Xinyi carefully raised the palm of the deceased and began to observe it carefully.

And this look... His face changed instantly.

"What, what's wrong?" Mao Lilan asked a little nervously.

Lin Xinyi didn't answer, but first smelled the smell of the dead man's hands.

Of course, it's not a very unprofessional way to take the dead man's hand to his nose and sniff it.

The way the forensic doctor smells is actually the same as that taught by the chemistry teacher in junior high school. Gently fan the air with your hands to let a very small amount of gas float into the nasal cavity:

"bleach…"

Lin Xinyi's expression was very serious:

"The bastard washed the dead man's hands with bleach."

Chapter 187

After Lin Xinyi came to this conclusion, he suddenly got up and searched the bathroom carefully.

Sure enough, without much effort, he found a bucket from the corner of the bathroom.

Those are the plastic buckets that the cafe staff use to clean up.

Taking a closer look, there was still half a bucket of bleach in it that hadn't been poured out at all.

"It appears that the killer poured bleach into this bucket and soaked the dead man's hands in it."

Lin Xinyi said so, and then looked at the bleach bottle on the ground beside him:

"As for the bleach, the murderer should have taken it from the bathroom."

"Bleach is a regular toilet cleaning product in the bathroom. The murderer probably saw the bleach in the corner of the bathroom during the murder and thought of using it to clean up the traces."

As he analyzed in detail, his brows became more and more wrinkled.

And Mao Lilan on the side thought carefully for a while, and then asked a little ignorantly:

"Mr. Lin, I remember you said that bleach seems to be used for..."

"Can be used to damage DNA."

Lin Xinyi frowned tightly:

"The main component of bleach is calcium hypochlorite. After it is mixed with water, it reacts with water to form hypochlorous acid."

"Hypochlorous acid generates free radicals, and excess free radicals, especially reactive oxygen species, can attack almost all biomolecules, including DNA."

"Specifically, free radicals can damage the base modification of DNA molecules and cause DNA single/double strand breaks."

"Anyway, if the murderer washed the dead man's hands with bleach and soaked them for longer than a certain period of time..."

He paused slightly, and his tone became more serious:

"Then we probably won't be able to detect enough DNA fragments to support the identification results from the contents of the deceased's nails."

Hearing this, Mao Lilan's expression quickly became more serious than that of Lin Xinyi:

Even the DNA has been destroyed, so there is no evidence to catch the murderer?

How to do this?

But seeing her nervous and serious expression, Lin Xinyi smiled and shook his head instead:

"Don't be too nervous."

"Even if the biological material in the nail is destroyed, can't there be other evidence?"

"When the murderer strangled the deceased, the two bodies were close together."

"In addition to fingernails, it is also very possible that hair and dander rubbed against each other on the clothes."

"And those traces are not visible to the murderer with the naked eye."

With that said, Lin Xinyi also said meaningfully:

"Not to mention…"

"The murderer has worked so hard to clean up the traces, but there is no silver 300 taels here."

"This..." Mao Lilan quickly realized.

She remembered the process of confronting Tomoshi Tanaka yesterday, and immediately came to a conclusion:

"This case is also committed by an acquaintance?!"

That's right, the robbery kills that happen randomly, very few people will deal with the traces after the kill.

Especially, in a public place like a coffee shop bathroom.

After all, the murderer did not know the deceased. Even if DNA was left at the scene, it would be difficult for the police to find him in the crowd.

But the crimes committed by acquaintances are different: they are often closely related to the deceased. In order to prevent the police from investigating themselves, they wish to clean the scene cleaner than the dust-free operation room.

But this is often self-defeating.

Because the act of cleaning up the traces will inevitably arouse the suspicion of the police, and when the police target the suspicion on a certain person, that guy is not far from a life of having enough clothes, housing, food and drink.

After all, human intelligence has its limits.

No matter how careful a person is, there will always be omissions that he does not notice.

"Miss Maori, you are right. Most of this case is committed by an acquaintance."

"Next, as long as we investigate the social relationship of the deceased, it should not be difficult to locate the suspect."

Lin Xinyi generously praised Mao Lilan who reacted quickly:

"but…"

"But we, as forensic doctors, can never be preconceived."

There is no need for Lin Xin to emphasize again and again, the good student Mao Lilan has already completed the quick answer:

"I know, Mr. Lin."

"The current case points to an acquaintance committing the crime, but the possibility of robbery and murder or impulsive killing cannot be completely ruled out."

"To rule out the possibility of the latter, we have to carefully observe the situation at the scene."

As he said that, Mao Lilan carefully looked at the narrow and crowded toilet compartment, and soon turned his gaze to the window on the wall of the compartment.

The windows are open, allowing access to the outside world from this compartment.

"When we found the body, it was right next to the door, blocking the door from the inside."

"So, if the murderer killed someone in this toilet cubicle, there are only two ways for him to leave the cubicle after killing someone:"

"One, escape directly to the outside of the coffee shop through the window in this compartment."

"Second, turn out from the gap between the top of the cubicle and the ceiling, then leave the bathroom, and leave from the inside of the cafe."

"But, this first possibility..."

While analyzing for himself, Mao Lilan moved to the narrow window and carefully observed the dust on the edge of the window:

"This first possibility is no longer likely."

"The dust accumulated on the edge of the window has not even been wiped. The murderer must not have left here."

"Besides, the window is very narrow, so even a girl like me would get stuck if I climbed out."

"If you want to flip out from the middle without touching the window frame at all, it is estimated that only petite children can do it."

As she said so, she quickly raised her head and shifted her gaze to the top of the toilet cubicle:

"The gap between the top of this compartment and the ceiling is relatively large."

"As long as it is a thin adult, it should be able to get out from here."

"only…"

Ms. Maori's smooth observation and analysis finally encountered a difficulty:

"The deceased was stabbed in the heart, and the amount of bleeding was so large."

"And this bathroom is so small that you can't dodge it."

"When the murderer drew the knife, there should be a lot of blood on his body."

"And a person with blood on his body came out of the bathroom, the employees and customers in the coffee shop should have noticed more or less."

She rubbed her chin inadvertently while she was thinking, looking like a famous detective.

However, Lin Xinyi pointed out a direction of investigation:

"Speaking of blood, I also noticed something strange."

"First, there was blood on the door frame at the top of the toilet cubicle that wasn't supposed to be there."

"Secondly, it's the form of splattered blood in this compartment."