civil forensic

Chapter 135 High-end
late at night.

The owls are all asleep.

After listening to Jiang Yuan's words, he regained some energy as a technician.

In the small courtyard of the old man who scavenged waste, at the position where he just entered the door, several technicians gathered together and stood behind Jiang Yuan, listening to him while observing the blood on the ground.

Under the illumination of the headlights, the color of the blood was a bit distorted, but the cruelty in it could still be vaguely felt.

The position of Jiang Yuan's finger is one of the few places on the ground that is not covered by objects in the courtyard. There are several blood spots, which are quite conspicuous.

"There doesn't seem to be any splattered blood here." Hou Xiaoyong has also studied blood stain analysis, but he is not good at the art and only knows some well-known knowledge.

Jiang Yuan only nodded his head lightly, and said: "The book says that the splattered blood often indicates the first scene and the starting position of the harm. But at today's scene, the lethality of the murder weapon used by the murderer is obviously not enough. , which shows from another aspect that the murderer's original purpose may not be to kill people."

Jiang Yuan compared it on his head, and said again: "From the throwing bloodstains around, it can be seen that the murderer should have used a blunt weapon, and look at the speed of the throwing bloodstains. Look at this It's more obvious on the side walls."

Everyone gathered around to look at the blood on the wall.

On the wall made of red bricks and cement, there are mainly oval and long strips of bloodstains, and there are some small bloodstains in front.

"This is a relatively high-speed bloodstain feature, indicating that the blunt weapon is not heavy and may be relatively long." Jiang Yuan also analyzed while watching.

Several technicians nodded, indicating that they knew the well-known knowledge.

"So, his first blow probably didn't bleed. It didn't produce splatter-like blood." Jiang Yuan glanced at Hou Xiaoyong, and answered his question.

Hou Xiaoyong couldn't help but nodded slowly.

Indeed, if you hit the forehead with a blunt instrument, it does not immediately bleed.

"But after being beaten, Zhang Hong, that is, the dead old man who scavenged waste, evaded. The blood on the handprint here was pressed later. It can be seen that he ran forward." Jiang Yuan said Then he pointed forward and said, "There is a throwing blood here, which means that the second blow broke the scalp."

Jiang Yuan took two steps forward, and there was a pile of collapsed objects in front of him.

"Here is the trace left by the seventh blow. Take a picture and bring up the blood evidence first. The rest can be put aside and brought up slowly later." Jiang Yuan waved his hand in front of him, delineating a period area.

Hou Xiaoyong and the others, who were following Jiang Yuan to learn how to reconstruct the crime scene, were taken aback for a moment, a little at a loss.

"You ask."

"You ask."

Several technicians exchanged glances.

The senior technician, who was tired of winking back and forth, immediately got angry with his eyes, and stared at everyone to signal: "Are you asking or not? I don't care if you don't ask. What do you pretend at this time? When you are asked Get up, which one of you will answer?"

Hou Xiaoyong sighed and asked aloud, "Jiang Fayi, what does the seventh time mean?"

"I judged according to the order of strikes at the crime scene. This is what was left during the seventh strike." Jiang Yuan replied.

Hou Xiaoyong opened his eyes wide, and said, "Didn't we just say that the first hit didn't bleed, the second time it did, and then it should be the third blow."

"The blood from the third blow, I guess, is on the ground, and you can only see it now when you lift it up." Jiang Yuan replied.

Everyone can understand this answer.

When the old man entered the door, the storage rack was still in good condition, and everything was placed on the storage rack. It was because of the attack of the perpetrator and the escape process of the victim that a large number of objects were removed from the temporary unstable storage rack. up and down.

Therefore, the blood from the third blow was buried by the objects on it, and anyone can figure it out.

The difference is, how did Jiang Yuan judge that the top one was the seventh blow?

Hou Xiaoyong endured it for a few seconds, but still felt that he couldn't take it anymore, and asked, "Let's not talk about the blood from the third beating, why do you say that it was the seventh time, not the sixth time, or the first time?" 10 times?"

Jiang Yuan smiled kindly, and said softly: "I counted it. I have already completed the reconstruction of the crime scene in my mind, and then I will tell you about it."

Hou Xiaoyong was stunned for a moment.

It was also because he stayed up late for too long that his judgment and IQ began to decline.

If he could sleep for 10 hours and 8 hours, he felt that he would be able to rebuild a few steps.

However, this is actually the misunderstanding of all the problems given to the scumbags.

Students who look at the teacher or other people's problem-solving steps, step by step, step by step according to the order of problem-solving, often have a misunderstanding, that is, I have learned.

In fact, students who read step by step and in order are still very far from learning.

Most of the math problems are actually not done step by step, but first look at the needs at the end or the middle, and then look at how to meet the needs at the end and the middle.

Just like the reconstruction of a crime scene, no expert in bloodstain analysis can really guess where the first step is and where the second step is, and guess it step by step.

Doing so is foolish and creates too much unnecessary burden on yourself.

It was like the first step. According to the information Hou Xiaoyong had learned, it seemed that he should look for splattered blood, but according to Jiang Yuan's judgment, the first blow did not bleed. What's the matter?
As far as Jiang Yuan's second step is concerned, it is similar. If you want to find the second blow, should you look at the bloodstains and analyze them?Then the possibility of other bloodstains being the second blow has to be ruled out.

Too much trouble and unnecessary.

The correct approach is to first judge whether the bloodstain is in the early stage, the middle stage, or the late stage, or whether it is before or after the iconic event.

Arranging the positions of the identified bloodstains, and slowly filling in the remaining bloodstains is a relatively simple problem-solving step.

Not enough, this kind of crossword puzzle needs to be controlled as a whole. To a certain extent, if the crime scene cannot be completely reconstructed, it cannot be built half of the crime scene.

Hou Xiaoyong and other technicians have not actually received training in reconstructing crime scenes.

There are many ways for criminal science and technology personnel in China to learn things. The most common but most basic ones are the courses in schools. These things are the foundation of the foundation and may not be used in practice. , the subsequent development potential is very low.

For example, for the same bloodstain analysis, it will use some high school physics and chemistry knowledge, such as momentum, angular velocity and the like. In fact, high school students need to spend several months and hundreds of questions to understand.

If a criminal science and technical personnel does not have the corresponding knowledge, it is unlikely that the level of understanding will be the same.

In addition to the school's learning path, reading books and learning from teachers in the work unit are the two most common modes.

In addition, various training activities organized by various units have gradually become the mainstream of technical personnel promotion.

Techniques like extracting DNA from sweat sound simple and commonplace these days.

But this was also promoted around 08, and before that, not only the technicians could not do it, but the equipment and drugs in the DNA laboratory might not support it either.

For example, reconstruction of a crime scene is too high-end. It is basically difficult to practice the above routes except for a master.

So I keep acting in TV dramas because I feel awesome.

The bloodstain analysis of the primary form, etc., will be talked about during the training, but Hou Xiaoyong and others are not particularly eager to learn models.

In general, when Jiang Yuan said that he had completed the reconstruction of the crime scene, several technicians were lost in thought.

Most of them were thinking: How is he going to lie to us?
Jiang Yuan waved his hand and said, "From here, take another layer."

Several technicians wore gloves without saying a word, and took another layer of objects.

"Not yet, then take another layer."

Everyone follow suit.

Objects stacked on top of each other bring pressure to technical geeks, just like three girlfriends looking for cash at the same time.

"This should be the trace of the third blow." Jiang Yuan himself also marked it in the notebook.

A few people looked over and didn't know why, but they could only trust Jiang Yuan.

Divide 857 by 648, if you can't figure it out, then you can only listen to the result after hearing what other people said.

"Here's where the late hits go."

"The location of the bleeding is very particular."

"From here, the murderer entered a state of hyperactivity."

Jiang Yuan described the crime scene intermittently. Unlike acting, his most important job now is to collect evidence.

After digging like this, a small blood spot attracted Jiang Yuan's attention.

"Wait." Jiang Yuan stopped the technician who was about to step forward.

"what happened?"

"This blood spot, look at its landing point and speed. It is not the same as other nearby blood spots." Jiang Yuan took a look and noticed this blood spot.

It's just that at this moment, the other technicians all stared blankly.

There's no difference here, they obviously look the same...

"The trajectory of all the blood spots in the air is basically a parabola. If this blood spot comes from the dead, it is likely to cut a smaller corner."

While Jiang Yuan was talking, he asked someone to take several photos.

"Do you suspect it was brought by the murderer?" Hou Xiaoyong heard the meaning.

"At least it was the blood that splashed on the murderer, and then splashed out. But the biggest possibility is that it was the murderer's own."

Jiang Yuan said that he did it himself, and carefully took the blood spot in front of him.

Hearing what he said, there was a commotion among the other technicians, and they gathered together to stare again.

"Is the murderer injured? How did he get injured?" Hou Xiaoyong asked anxiously.

Jiang Yuan glanced at him and said in a low voice: "During the crime, the deceased may have resisted, maybe something was splashed and hit somewhere, maybe the murder weapon injured himself..."

Jiang Yuan didn't mean to explain. For him, a drop of blood is enough to decide many things, and there is no need to demand full blame.

Someone left blood at the scene of a violent crime, so no matter who he is, he should come to the police station to explain the situation!
　Trying hard to code, meow
　　
　
(End of this chapter)