2 o'clock in the morning.

There are no street lights. From time to time, a car will pass by on the road, its headlights are glaring and its sound is harsh.

There are a few stars in the sky, and the total number is probably a few more than what you can see in the city. But few people will look up, and even fewer people are leisurely counting stars. Even the children are immersed in the table.

Before, I no longer had any thoughts.

There is still a hot smell coming from the surroundings, not the real temperature, but more of an anxious atmosphere.

Just like those workers who have finished the night shift, most of them have exhausted faces.

The people who sell late-night snacks on the roadside have serious expressions on their faces. They try hard to attract people and then withdraw their arms in a perfunctory manner.

The wild dogs wandering around looked at the passers-by and were too lazy to beg for food. People who were off work during this time were not enthusiastic enough to feed the dogs, and they were not willing to take risks and act cute.

Among the people passing by, many people were looking at the screens of their mobile phones. Some people were riding electric bicycles, still holding their mobile phones in their hands to look at them. They were shaking their handles left and right without paying attention. From time to time they lost control of their balance.

Stop on the side of the road and look at your phone for a while before leaving.

In the yard of the old man scavenging, the dazzling white lights should have attracted a lot of attention, but most people just took photos and left, not even interested in watching.

There are too many hot spots and too many melons for everyone to eat.

The locals themselves don't care too much about what happens in the urban village. Those who like to post videos and Moments online are not very happy to locate the location in the urban village.

The death of an old man scavenging did not cause any waves.

Jiang Yuan couldn't help but recall the life in Jiangcun before it was demolished. At that time, although everyone was poor, they really had a lot of time.

Although he is lazy and poor, he has a leisurely and happy atmosphere.

But life in the urban villages of Longli County is different. The people here are not only poor, but also have no time.

The entire urban village is in a state of being left over from demolition and demolition.

There is no hope.

The air is filled with exhaustion and helplessness.

Young people who return to their hometowns to start businesses do not get anything extra except being close to home.

Jiang Yuan sat under the tree and drank a bottle of water. His whole body still felt very tired.

However, he is young and does not feel like he is about to die suddenly, so he should be able to work all night long.

Jiang Yuan looked at the technicians of the Criminal Science and Technology Squadron in Longli County not far away and felt helpless. They were working hard and busy like worker ants in an ant nest, but there was no end in sight to their work.

Jiang Yuan couldn't help but sigh.

The skills of these technicians may only reach LV0.8.

If they are serious enough, the probability of finding the murderer's DNA in a limited area is still very high, assuming that the murderer did leave DNA behind.

However, human energy is limited, especially when it comes to focusing on small details for a long time.

The difficulty of the old man's courtyard is almost like adding cubes.

In another case, it might not be so obvious.

If an ordinary husband in an ordinary family violently assaults an ordinary wife to death, then the ordinary home environment is usually 2D level.

If you customize the whole house and kill people in the customized room, it will be equivalent to 3D level at best.

Assuming that it costs 150,000 yuan to customize the whole house, then killing someone in a room that is customized to the whole house will waste an extra 50,000 yuan of police funds for the case, which is a huge expense.

But what is the structure of the small courtyard for the old man scavenging?

4D!

There is not only a plane, but also a height, and there is also information such as blood stains and DNA between the objects.

In other words, when wiping evidence in the old man's yard, you not only have to wipe the surface, but you also have to pick up those complicated objects and wipe the inner parts.

Where the old scavenger was beaten, objects were struck repeatedly, covering previous evidence repeatedly, creating an astonishing complexity.

If you want to be more detailed, you have to consider the time factor, because each object falls at different times, and there is a sequence, so different evidence will be contaminated at different times.

Finally, and most importantly, even if the LV0.8 technicians present can detect the murderer's DNA, how can they prove whether it was contracted on the day of the incident or beforehand.

If he were to switch to Jiang Yuan's LV4 crime scene investigation, he might have some ways to distinguish, but for technicians below LV1, it would be useless to think about these things.

Moreover, even if Jiang Yuan had LV4 crime scene investigation, he did not want to use it to make similar distinctions.

It's too complicated. How can I explain it to the judge and prosecutors during the litigation process?

Therefore, Jiang Yuan felt that the best way to prove it was to stare at the blood stains and the murder weapon.

Furthermore, despite the fact that these men are so weak and bent after wiping DNA, it is more difficult for their results to be effective than wiping DNA.

Jiang Yuan decided to save them... and save himself at the same time.

Jiang Yuan returned to the old man's courtyard, stood at the door, looked at the busy sounds of a group of technicians, coughed twice, and said, "I have an idea."

A group of numb technicians stared at Jiang Yuan with dull eyes.

"I want to prioritize looking for blood evidence and see if I can find the blood stains left by the murderer."

Seeing everyone looking over, Jiang Yuan continued:

"If that doesn't work, you can also use blood stain morphological analysis to determine which objects the murderer has touched at the scene, thereby narrowing the scope of DNA testing."

Bloodstain morphological analysis is equivalent to reconstructing the crime scene.

By reconstructing the crime scene, you can "see" the murderer's route in the scavenging yard, as well as most of his actions.

As a result, objects that are relatively close to the murderer are more likely to be contaminated with the murderer's DNA.

The expressions of several technicians ranged from numb to a little excited and then a little numb again.

"This is different from the tasks assigned to us by our superiors."

A surveyor named Hou Xiaoyong spoke out first.

Jiang Yuan said calmly:

"The task given to you by the criminal police team cannot be to wipe the DNA in a certain order. When conducting on-site investigation, there are already priorities. How to grasp it should not be within the scope of the on-site investigation's responsibilities?"

Several technicians were very tough, and they didn't expect this young forensic doctor from the next county to be so tough.

One of the older technicians, Lao Li, couldn't help but stand up, took the opportunity to stretch and twist his waist, and said: "Xiao Jiang, what if the DNA is missed or contaminated according to the method you said? Who is responsible?

"

The other young technicians in Longli County were a little embarrassed to bow their heads. Their technical skills were originally weak. On the one hand, their skills were not good, and on the other hand, their kicking ability was too strong.

Now he actually had to hand over the ball to the forensic doctor from another county. The young technician was a bit shy, especially since he had just eaten the food given by Jiang Yuan and smoked his good cigarettes.

"In this current environment, which DNA is not contaminated?" Jiang Yuan asked.

Two technicians laughed without even blinking.

Indeed, at this site, there is no talk of contamination. The scavenged objects are all covered with unknown DNA.

so many people……

The tall and young Jiang Yuan is still relatively eye-catching among a group of people.

He said loudly:

"In this environment, blood stains are the best way to prove your identity. It's all a bet anyway. If I had to choose, I would definitely bet on the murderer in the blood stains first. Thirdly, betting on the morphological analysis of the blood stains is better than betting on the scene.

"

Several other technicians looked at each other, hesitating a little. They didn't want to rub DNA like this until they died, or they might be doing useless work, and they would still be scolded in the end.

"And doing the blood stains now is to preserve the most important evidence first. Anyone who conducts on-site inspections and makes such a decision will be absolutely correct. No matter where they go for review, they can't find a single mistake. Or, you guys

Call me for instructions?"

Although Jiang Yuan is young, he is not a fool. He is here to help, not to take the blame. He kicked the ball back.

Several technicians also preferred Jiang Yuan's words.

It's better to have a direction than to do it hard here.

Several people looked at each other.

The young Xiankan Hou Xiaoyong asked again:

"Forensic Doctor Jiang, can you reconstruct the crime scene?"

"meeting."

Jiang Yuan's answer was brief and powerful.

"Reconstructing a crime scene is not easy..." Hou Xiaoyong couldn't help but muttered.

The person who is closest to blood morphology analysis is naturally Hou Xiaoyong, who is doing the spot survey. However, he only knows a little bit about it, and he is far away from reconstructing the crime scene.

The kind of people who analyze the scene as soon as they see it on TV are very reasonable...the reality is actually very little, and it's a bit nonsense.

The work of reconstructing a crime scene is no longer just a matter of ability, it also involves issues of face, image, and even status.

When the reality is broken, the crime scene is reconstructed, and the scene where the murderer killed or attacked the victim is reconstructed. Although it is cool, on-site investigation requires completing the scene reconstruction step by step, and then writing the process in detail, forming thousands of words.
To be continued...