"Chirp chirp chirp~~"
As the sun rises in the east, the temperature in Beijing has risen significantly in recent days.
The sparrows outside the window were chirping on the branches.
Outside the laboratory, a group of police officers looked at Shen Ting, who had already started operating in the laboratory, and their discussion was noisier than sparrows.
The scene didn't quiet down until Qian Duoduo spoke up to stop it.
However, he was actually feeling quite nervous.
Looking at Director Su in the Trace Inspection Office, I couldn't help but ask:
"Director Su, what do you think is the probability of Shen Ting extracting fingerprints from carbonized leather?"
"this……
I wouldn't dare to say that Shen Ting will fail 100%.
But Captain Qian, I advise you not to hold your hopes too high."
Director Su looked at Shen Ting's operation and nodded.
"He is quite skilled in using the instrument..."
But then he shook his head:
“However, the problem now is that fingerprints on carbonized leather cannot be extracted due to limitations in methods and technology.
It’s not a question of instrument proficiency!
What's more, let's take a step back!
Even if Shen Ting could really extract fingerprints from carbonized leather.
Since the leather is severely carbonized and has fallen off in large quantities, the extracted fingerprints are bound to be incomplete.
In addition, when salt penetrates into carbonized leather, it is impossible to completely maintain its original shape.
The extracted fingerprints must be severely deformed.
That is to say, the fingerprints that Shen Ting finally obtained must be incomplete and deformed.
This is actually the same as fingerprints extracted from bomb fragments and broken plastic.
It has no significant value to the case.”
“To put it simply!
Leather is one of the oldest living materials used by humans.
The specificity of fingerprints was discovered and used to solve the case.
Fingerprints exist on leather, but due to high-temperature carbonization, the fingerprints cannot be extracted. This situation is definitely not uncommon.
But the fact that this problem has not been solved yet is telling.
Researchers all over the world have not been able to solve it for such a long time.
The root cause is that fingerprints on carbonized leather are not only difficult to extract, but even if they are extracted, they are incomplete and of little significance to solving the case."
“Is that so?”
Qian Duoduo nodded.
After listening to Director Su's explanation, he realized that the intricacies involved were much deeper than he had expected.
but!
Deep down in his heart, he was still willing to believe Shen Ting.
After all, Chen Ting is the person who solved two consecutive cases: the disappearance on a snowy night and the cardboard man.
Regardless of previous achievements, let’s just talk about this case.
It was Shen Ting who first found Xu Tuanjie's mistress, and it was also Shen Ting who first found Zhang Haisheng, the owner of the suspicious phone.
even!
The owner of the leather jacket and Xu Tuanjie's body were both found by Shen Ting.
“Director Su, I still feel that Shen Ting is okay.”
Director Su rubbed his eyebrows and sighed:
"Why wouldn't I want to believe him?
But my decades of experience and my brain that has observed and compared thousands of fingerprints tell me that it is impossible!
It's impossible to extract fingerprints useful for solving a case from leather that's been carbonized to this extent!"
His tone was a little tired:
"Captain Qian, I understand your urgency to solve the case, but extracting fingerprints from leather carbonized to this extent is a difficult problem in the international trace detection community.
Not to mention the distant past, two months ago, in the "Qingshi Goose Farm Arson Case" in Zhejiang Province, the leather guardrail was burned to a degree similar to this leather jacket.
At that time, the Ministry of Public Security dispatched three trace detection expert groups to try various extraction technologies such as vacuum coating, ion sputtering, and even laser-induced fluorescence, but what was the result?
The extracted fingerprints are full of distorted noise, and even the direction of the lines cannot be distinguished.
Last year, the Forensic Science International Journal (FSI) published a review that counted 21 carbonized leather fingerprint extraction cases worldwide. All of them were severely carbonized leather, and the extraction success rate was 0.
Why?
Because once the leather is burned, the fingerprint salt crystals get stuck in the cracks of the carbonized layer.
But the salt stain has no grain details!
Even if Consultant Shen can really come up with some fingerprint traces, they are not fingerprints. At most, they are the outline of fingerprints made up of salt grains. They can't even be considered a chain of evidence in court..."
"But didn't I mention before that there were cases of successful fingerprints being deposited on carbonized wood?"
Qian Duoduo was interrupted by Director Su before he finished speaking:
“It’s different!”
He pulled up a comparison chart from his phone and showed it to Captain Qian:
“The principles behind the two are different!
After carbonization, the wood has a uniform structure and fingerprint salts can penetrate along the growth rings.
However, after the leather is carbonized, the crack width exceeds 50 microns, and the salt crystals will shatter when pressed, and the details of the ridges cannot be retained at all.
Captain Qian, I also hope that this case can be solved as soon as possible.
But science is science, and some technical barriers cannot be overcome simply by 'trying'!"
…
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