I am a super cop

Chapter 822 Exceptions
Testing room.

After Gu Chen finished extracting the dirt from Wang Jinshan's ten fingers, He Wenjun stepped forward and asked, "Do you know what this is?"

"It's hard to say now." After sealing the small transparent evidence collection bag, Gu Chen marked the number on the label paper, and then said: "Further testing is needed, because the dirt is in powder form. At least I can It will only be known after testing.”

Looking at Gu Chen's suspicious expression, Liu Zhiqiang asked, "Could the dirt between the nails be left by Wang Jinshan when he scratched it?"

"Perhaps." Gu Chen said very simply, but let out a long sigh.

This caught He Wenjun's attention.

He Wenjun asked Gu Chen, "What are you feeling? Is it because the deceased knew you?"

Gu Chen shook his head: "No."

"Then why are you?" He Wenjun heard that there was something in Gu Chen's words.

Gu Chen didn't answer right away, but put the evidence collection bag on the parallel testing platform, then turned around, and said to He Wenjun:

"You speculated that the deceased Wang Jinshan died while swimming while drunk. I don't think so, because according to the time of death, He Wenjun died around the early hours of last night."

"But you have to know that the last time I saw Wang Jinshan was at dinner time."

"Although he was drunk at that time, after we gave him milk, his condition gradually improved."

Looking around, Gu Chen said again: "When he left, his consciousness had already begun to wake up."

"But in such a state, how could he get drunk and drown in the swimming pool around midnight?"

"Unless there is a possibility that he drank again at home, so I would like to ask, have you found any traces of Wang Jinshan drinking in his home?"

"This……"

When Gu Chen asked him suddenly, He Wenjun froze for a moment, shook his head and said, "I didn't find out, it's just because we found out that Wang Jinshan drank alcohol last night, so we are only making a rough guess."

"That's uncertain." Gu Chen said affirmatively.

Liu Zhiqiang on the side frowned, and turned to ask Gu Chen: "Officer Gu, how do you know that the deceased Wang Jinshan died around the early hours of last night? The teacher hasn't come to a conclusion yet, how can you conclude that it was the early hours of last night?" ?”

"There's no need to judge." Before Liu Zhiqiang finished speaking, the instructor Zhang Hui stood up straight, and said with a deep breath: "Gu Chen is right, the time of death was indeed around midnight last night."

"Really...really?" Liu Zhiqiang couldn't believe it. He turned to look at Gu Chen, but he didn't understand, so he said, "But... Gu Chen just came in not long ago. He was just observing the corpse. How could he do it so quickly?" Determine the time?"

Glancing at Zhang Hui, Liu Zhiqiang said again: "Even your teacher Zhang hasn't completed the comprehensive test yet, why...how can he..."

"I don't know, but what he said is right." Zhang Hui shook his head and smiled, turned to look at Gu Chen and asked, "Gu Chen, how did you know the time of death of the deceased? I just finished testing the specific characteristics."

"And you just scraped off the dirt from Wang Jinshan's fingernails, so you can determine the time of death?"

"Of course not." Gu Chen shook his head directly, and explained: "Actually, to identify the cause of death, I also judge based on previous experience."

"Experience?" He Wenjun was a little surprised. After all, the autopsy work has always been done by the forensic team.

Gu Chen is not a forensic doctor, yet he talks about his experience here?
He Wenjun felt a little incredible.

Gu Chen pressed the corpse with his fingers to show it to everyone: "Actually, to determine the time of death, you can generally determine it from three directions. The first is to look at the stiffness of the corpse."

"That's right." Instructor Zhang Hui agreed with Gu Chen's opinion and nodded slightly: "This is a method that our forensic doctors usually use to detect corpses."

Glancing at Gu Chen, Zhang Hui asked again: "Then what is your criterion?"

"It's very simple." Gu Chen poked the corpse with one finger, and said: "Under normal circumstances, the corpse will harden between 30 minutes and 2 hours after death, completely ossify between 9 and 12 hours, and soften after 30 hours. However, after 70 hours, it will return to the original state."

Seeing Zhang Hui nodded slightly, Gu Chen said again: "But it is worth noting that if you are in soil or water, or in low-temperature and dry conditions, it will be delayed, and it will be accelerated under high-temperature and humid conditions."

"I also made a judgment based on these foundations and some previous experience."

"Yes." Zhang Hui was satisfied with Gu Chen's answer.

I was also using these data to compare the corpses before, and deduced that Wang Jinshan's death time may be around the early morning.

But Gu Chen can also judge it extremely quickly, which makes Zhang Hui look at Gu Chen differently.

He Wenjun and Liu Zhiqiang also looked at Gu Chen differently.

The two were colleagues with Gu Chen, but most of them relied on the forensic team for the autopsy.

But being surpassed by this young colleague in front of them, everyone felt a little embarrassed.

Liu Zhiqiang couldn't help but joked: "It's quite reasonable, so besides this, what other basis can you use to judge the time of death?"

"Too many." Gu Chen pointed his fingers and explained to everyone: "We also judge by the temperature of the corpse."

"Generally speaking, within 10 hours after death, the temperature of the corpse drops by 1 degree per hour, and after more than 10 hours after death, the temperature of the body drops by 0.5 degrees per hour."

Hearing Gu Chen's words, He Wenjun and Liu Zhiqiang looked at Zhang Hui together.

Zhang Hui also nodded silently, agreeing with Gu Chen's words, and still calculating the corpse based on the data provided by Gu Chen.

"So... you took the tool just now, in addition to extracting the dirt from the crevices of the nails of the corpse, you also conducted a temperature test?"

"That's right." Gu Chen nodded slightly and admitted: "The temperature of the corpse was indeed tested just now, otherwise it would be difficult to judge the condition of the corpse."

"Then there is another direction?" Zhang Hui realized at this moment that Gu Chen seemed far from being as simple as he imagined.

It seems that this guy is quite familiar with the forensic work business.

Gu Chen blurted out directly: "There is also a judgment based on the purple-red plaques that appear on the skin under the corpse after death, that is, corpse plaques."

“因为尸斑通常在死亡后2小时至4小时出现，经过12小时至14小时发展到最高度，24小时至36小时固定下来不再转移。”

"However, the occurrence and development of general corpse phenomena are greatly affected by internal and external factors, so all conditions should be comprehensively analyzed objectively."

"That's great." Zhang Hui grinned, and said involuntarily, "Gu Chen, I didn't expect you to be able to judge the death time of the deceased simply by passing these conditions. This is very rare, and it shows that you have put in a lot of hard work. .”

"Of course." Seeing that Zhang Hui, the instructor, started to praise Gu Chen, Lu Weiwei was overjoyed and said, "Instructor Zhang, I have long said that my junior brother Gu knows a lot about this business, don't you believe me?"

"No, no." Zhang Hui interrupted Lu Weiwei and said, "It's not that I don't believe it, it's just that Gu Chen is too young, logically speaking, he must not be familiar with the autopsy business."

"At least in my opinion, young forensic doctors are more or less flawed in detection."

"Perhaps there are some people of the same age who can accurately determine the cause of death like Gu Chen, but it is very rare for people who can make a preliminary judgment as quickly and accurately as Gu Chen, at least I still can't." Never met before."

"It's really amazing." Liu Zhiqiang couldn't help admiring, even Zhang Hui was full of praise for Gu Chen, which shows that Gu Chen's business is really solid.

Such a generalist is rare in the police force.

He Wenjun also smiled and said: "Gu Chen, so you are so familiar with these forensic work? No wonder you rushed to come to Mr. Zhang to help. I really underestimated you just now."

"Actually, I didn't want to rush to come here to help." Before He Wenjun finished speaking, Gu Chen directly interjected, "The main reason is that the deceased had contact with me, and I know some things about him."

"Come here, maybe I can provide you with some ideas for handling the case, so... this is the purpose of my coming to the testing room."

Hearing Gu Chen's remarks, He Wenjun and Liu Zhiqiang looked at each other in blank dismay, and they couldn't help giving their thumbs up.

"It seems that you are in the right place. Welcome to join the case handling team. I hope you can help us in the testing room as much as you can."

Previously, He Wenjun still had doubts, wondering why Gu Chen appeared here?

But the current He Wenjun no longer has any objections to Gu Chen.

Gu Chen also nodded slightly to express his gratitude.

At this time, Zhang Hui took the nail dirt extracted by Gu Chen and prepared to test it on the testing platform.

Police Officer Wang said a lot: "If Wang Jinshan drowned in his own swimming pool, then unless the dirt is on him, there is something wrong."

"It's not a problem, but a big problem." Gu Chen directly corrected Police Officer Wang: "In my opinion, these dirt are more like some soil, gravel and plant debris."

"what do you mean……"

He Wenjun frowned slightly upon hearing Gu Chen's remarks.

"That's right." Gu Chen didn't shy away from it, and said directly: "When a person is drowning, he will try his best to grab anything around him and try to survive."

"So drowning people often hold dirt, small stones, plants, etc. in their hands, and they can often be found in their nails. These things can also be used to determine the exact location."

"If a body is found in a swimming pool, and if the forensic examiner finds debris in the lungs or in the fingernails that was not in the swimming pool, then it is possible that the deceased drowned elsewhere and was later disposed of in the pool. , pretending it was an accidental drowning."

"Junior Brother Gu means... the swimming pool in the deceased Wang Jinshan's home may not be the first scene?"

"Yes, that's what it means." Gu Chen nodded slightly, and said indifferently: "If we can compare the specific origin of the substances contained in the debris, such as pollen, feather seeds, etc., it may be able to explain that the deceased drowned there of."

"What you said makes sense." He Wenjun agreed with Gu Chen's opinion.

But as a colleague, He Wenjun couldn't help but say a few more words, and by the way educate Liu Zhiqiang beside him:
"Actually, during an autopsy, is it possible to tell where a drowned person drowned? For example, in a bathtub or in a river?"

"If it is possible, to what extent it can be clarified, the deceased needs to be carefully inspected. Gu Chen just scraped the dirt from the crevices of the deceased Wang Jinshan's fingers is a good way."

"Yes." Gu Chen nodded slightly, also took off the contaminated gloves and threw them into the trash can beside him, and then said:
"When a person drowns, they inhale water and substances contained in it into their mouth, nose, throat and lungs."

"And such material includes leaves, insects, seeds, pollen and other debris."

"In cases of drowning in rivers or other natural bodies of water, it is possible that the animal and plant material found in the lungs of the deceased may be specific to a certain area."

"It's like finding pine pollen or pine needle fragments in the lungs, indicating that the victim drowned near water where pine trees grow."

"Even if it is replaced with other trees and other plants, it is also established."

After a pause, Gu Chen said again: "Insects also have a specific distribution area, so finding insects in the lungs can also hint at a specific place."

"All tests are subject to change, and it is right to follow this standard."

"But..." Hearing this, Liu Zhiqiang hesitated, and asked Gu Chen: "But the water in the swimming pool is usually quite clean, so there are no other clues?"

"It's also possible." Gu Chen seamlessly connected, and said directly: "The water in the swimming pool is usually quite clean, but most of it contains chlorine, but this can be tested."

"Natural waters do not contain chlorine at all. As early as the 60s, humans may have carried out this test, but it is not common."

Looking at Liu Zhiqiang's pensive look, Gu Chen said again: "So, for example, the water in the bathtub should be very clean and chlorine-free, but it may contain some soap or grease, and these can also be tested."

"So the substances contained in the inhaled water can often be used to help determine the location of drowning."

"I see. No wonder Mr. Zhang asked us to take water samples from the swimming pool. That's why."

"Haha." Listening to Gu Chen's explanation to the two, Zhang Hui, who was sitting on the testing platform, couldn't help smiling, and reminded him:

"You probably almost forgot about me and what kind of expertise I do."

"How can it be?" He Wenjun glanced at Zhang Hui, and also took the initiative to show his favor: "You are an expert in diatom detection, what can I do if I don't ask you to cooperate?"

Zhang Hui on the testing platform smiled and said jokingly, "You really can't do it without me."

"It should be said that since the German scientist Revenstorf used a microscope to detect diatoms from lung drowning in 1904, forensic workers at home and abroad have conducted in-depth research on diatom detection methods."

"But in fact, you don't know that our country began to conduct research on diatom inspection in the 30s."

"In the 60s, six provinces in central and southern my country conducted joint research on how to improve the detection rate of diatoms. My father was a member of the diatom detection team."

"So that's the case?" Lu Weiwei was also surprised, and couldn't help complaining: "So instructor Zhang is from a family of forensic doctors? They all eat this bowl of rice."

"Haha, it's okay, it's mainly influenced by my father." Zhang Hui didn't care about this, and wanted to show off his knowledge in front of everyone.

It doesn't matter if you don't say it, Gu Chen couldn't help it, and said directly: "Yes, I have read the relevant documents, but I didn't expect that there was instructor Zhang's father in the diatom detection team in the early years."

"That was still a very distant time, so it's worth not mentioning it now." Instructor Zhang Hui took out another sample after testing one sample.

Gu Chen said lightly: "I remember that in 1998, Canadian forensic pathologist Michelle Berlangen made the first test of diatoms in his book "Forensic Diatomology and Drowning". Scientific and forensic principles are thoroughly discussed."

"I also read that book a few months ago. The author of the book put forward the concept of forensic diatomology, which includes the principle, effectiveness, practicability of diatom detection and diagnosis of drowning, as well as diatom detection methods and procedures, etc. .”

After a pause, Gu Chen continued: "Because diatoms are gradually considered to be the most reliable markers for the diagnosis of drowning, diatom testing is also generally considered to be a relatively reliable means of diagnosing drowning, especially for the cause of death of rotting corpses in water. Diagnosis, considered the most effective method, is the 'gold standard'."

"Compared with the previous backward detection methods and rough experiments, this is already a great improvement."

Looking at Liu Zhiqiang and He Wenjun, Gu Chen said again: "When a person drowns, the diatoms in the drowning liquid will break through the alveoli and enter the blood of the human body for circulation. Among its brain and various internal organs."

"Therefore, today's diatom detection technology is mainly to identify whether there are diatoms in the body of the deceased."

"If the diatom detection technology in the internal organs of the deceased's dead body is positive, and the type of diatoms is consistent with the water samples on the ground, it can be determined that the deceased died of drowning."

"And now Wang Jinshan's body needs to verify this."

"However, there are many kinds of diatoms with different shapes, and the composition of diatoms in each water source is different." Instructor Zhang Hui glanced sideways at Gu Chen, and it was also an on-site test.

Gu Chen blurted out, seamlessly connecting: "Yes, there are many types of diatoms, but diatoms are single-celled organisms that are widely distributed in water. The cell walls are composed of a large amount of silica, which is extremely stable and hard. .”

"Therefore, as long as the qualitative and quantitative analysis of diatoms in the main organs of the corpse in the water can not only make a more direct judgment on the cause of death, but also point to the possible place of drowning."

"boom!"

As soon as Gu Chen finished speaking, the instructor Zhang Hui's arm touched the tray where the utensils were stored, and there was a sudden thud.

"Instructor Zhang, are you okay?" Gu Chen's eyes were drawn to him.

Zhang Hui waved his hand: "It's okay, I just found some abnormalities, so I accidentally touched the tray."

……

(End of this chapter)