Chapter 1144 Discovering Clues
For things like on-site investigation, Lu Chuan still believed in his own judgment. The details of each investigation by the detective were different.
Lu Chuan had already seen in the file that the criminal police from the Tianzhou City Public Security Bureau also collected the fingerprints on the door, and there was nothing unusual in the comparison.
But if others didn't notice it, it doesn't mean that Lu Chuan didn't notice it. Otherwise, how could there be differences in business skills?
However, Lu Chuan also knew that it had been a week since the crime occurred, and Wang Hong still lived in the room every day, so many traces may not have been left at the crime scene at that time.
The fingerprints collected on the door handle may not be the fingerprints at that time. Even if the Internet celebrity opens and closes the door every day, the fingerprints will be covered. Even if there are some fingerprints at the time, they may be covered.
But it doesn’t matter. Collection is better than no collection, and it can also be compared with the fingerprints collected by the Tianshan District Criminal Police Brigade that day.
According to some details described in the file, the room was cleaned at that time.
The investigators from the Tianshan District Criminal Police Brigade did not collect the stranger’s fingerprints or footprints during the first investigation.
From this point on, the scene should have been cleaned.
However, there were obvious signs of turning over at the scene, but not all the cabinets were opened.
Otherwise, if someone committed a murder, or robbed and murdered, Wang Lili’s bank card worth more than 40,000 yuan would not have been left behind.
This time Lu Chuan's inspection started from the entrance door and scanned in inch by inch, not missing a single detail.
Including the gaps in every floor tile and every door gap, the debris was picked out and placed in collection bags.
This time, Lu Chuan conducted the on-site investigation in accordance with the standards of criminal cases.
On-site survey photography, on-site excavation, ultraviolet light irradiation, etc. are all done with great detail.
Following behind him was the investigating detective from the Tianshan District Criminal Police Brigade. He was the one who conducted the first on-site investigation at that time. This time he saw Lu Chuan, deputy director of the High-tech Zone Bureau, doing it himself. He quickly took out a small notebook to record some relevant information. detail.
They have heard of Lu Chuan's name for a long time, but unfortunately they have never had the opportunity to study with him. This opportunity is rare, but they cannot miss it.
Some other criminal police officers, including Wang Dongtian, were also carefully observing Lu Chuan's movements.
Wang Dongtian himself is also a criminal policeman. As a criminal policeman, sometimes he does not necessarily bring the investigation police with him when he goes to the scene, so the criminal policeman generally also has some on-site investigation techniques.
Moreover, the so-called fingerprint detectives and current detectives are gradually spun off in recent years as the development of criminal investigation technology has improved the competition for personnel.
In the past, field criminal police officers were basically doing these things part-time.
The reason why some more powerful criminal police officers are very good at solving crimes is because they are very delicate and can find some details at the crime scene that other criminal police officers cannot find.
Wang Dongtian was a leader here back then. He could always find something at the crime scene that others could not notice.
It is precisely these inconspicuous things, things that others tend to ignore, that Wang Dongtian can often find key information from these clues.
It is precisely because of this that Wang Dongtian was able to reach his current position step by step and became the deputy director of the Tianshan District Public Security Bureau.
Watching Lu Chuan doing on-site investigation now is simply a kind of enjoyment. Wang Dongtian is also following behind to watch and learn. Although there were traces of cleaning at the scene, Lu Chuan still firmly believed that as long as the murderer stayed at the crime scene, some material exchange information would inevitably be left behind.
When he was in the police academy, Lu Chuan took a course called crime scene reconstruction.
The so-called crime scene reconstruction is to infer the location information of the victim and the murderer at the time of the crime based on some details of the crime scene.
The most important law is Lockard's Law of Exchange.
Theoretically, as long as a person has been to a space, no matter how long he stays in this space, he will eventually leave some traces of himself in this space.
For example, smell footprints, fingerprints, etc.
Even if the other party cleans it, these traces cannot be completely eliminated. For example, fingerprints contain human sweat and grease.
Theoretically, although fingerprints can be interpolated, the remaining substances cannot be eliminated 100%, but current scientific and technological means are not yet able to 100% extract these substances.
For another example, the human body is in the process of metabolism all the time, and necrotic cells will fall off every moment.
These are invisible to the naked eye, and may not even be detectable with a microscope. The substances will definitely remain at the scene, but they are just that. See if you can discover it, or if you have the ability to discover it.
Facts have proved that Lu Chuan's on-site investigation ability is indeed stronger than that of most people.
Start from the entrance door and go in inch by inch. Lu Chuan did not miss any detail when advancing, including under the sofa, under the feet of the table, etc. Qin Chuan did not miss any detail.
The entire on-site inspection lasted for a very long time. Everyone watched Lu Chuan doing the inspection without saying a word, and an hour passed quickly.
What Lu Chuan was holding now was a piece of information provided by Wang Hong, which was the kitchen knife found on the refrigerator.
This kitchen knife is a bone-cutting knife that is not commonly used in Wang Hong’s family.
According to the internet celebrity, this kitchen knife is usually kept in the kitchen cabinet and is not often used, so he did not find it at the time, and the kitchen knife was still found on the top of the refrigerator. If he hadn't been wiping dust on the refrigerator that day, he probably wouldn't have noticed it.
Through careful observation, Lu Chuan found that there were separate gaps on the kitchen knife. Some were relatively fresh, but some were relatively old.
“This round curled blade should be left by chopping bones.”
Although there was no blood on the kitchen knife, just by looking at the gaps, Lu Chuan knew how they were formed.
According to the Internet celebrity, this kitchen knife has not been used for a long time. The old gaps should be left by cutting bones before, but what about the fresh gaps?
"Bureau Wang, in this case, I will take this knife back to the Criminal Investigation Detachment. The equipment at the current investigation office is relatively complete. There are some special trace evidence that can be identified through the equipment there. . ”
When Lu Chuan was working in the Criminal Investigation Detachment, a lot of equipment was updated. Basically, the most popular and cutting-edge equipment on the market was available in the Criminal Investigation Detachment throughout the province. They are all among the best laboratories.
(End of this chapter)