Chapter 24: Collecting Fingerprints from the Corpse

An hour later, a professional salvage team arrived at the scene.

For water-based recoveries, the Criminal Investigation Detachment has specialized partner teams.

Based on criminal investigation experience, while water-related cases do not make up the majority of cases, they are by no means insignificant.

Particularly in homicide cases, the proportion of bodies dumped in water can reach as high as thirty percent.

Beyond homicides, many other cases involve evidence—especially murder weapons—being thrown into the water.

Consequently, the Criminal Investigation Detachment frequently has a need for underwater salvage operations.

Wu Jingzhong was once a professional swimmer; after retiring, he established a salvage company.

His company has long been a partner of the Criminal Investigation Detachment.

"Old Wu, the situation down there isn't very clear. It could be a body or something else. Be careful during the recovery; try your best not to cause any damage."

Wu Jingzhong was in his forties with a rugged appearance. He patted his chest toward Ren Qiang. "Don't worry, I'll go down personally this time."

The body had already been transported away, and the autopsy needed to be expedited.

Lu Chuan also went back with them.

Since no identification documents were found on the body, Lu Chuan needed to return to collect fingerprint and DNA samples to see if the deceased's identity could be matched through the system.

Compared to collecting fingerprints at a fire scene, collecting fingerprints from a corpse is relatively simpler.

Of course, this "simplicity" depends on the degree of decomposition.

According to the forensic medical examiner's estimate, the time of death for the body submerged in water was approximately three days ago.

Furthermore, due to being soaked in water, the degree of decomposition was not high, though there was severe edema (swelling).

However, this still posed a significant challenge for fingerprint collection.

The hardest part of collecting fingerprints from a corpse is dealing with highly decomposed bodies—those that leak decomposition fluid at the slightest touch, where the entire body feels like a giant jelly. Those are the real nightmares.

***

The autopsy room.

The corpse lay flat on the autopsy table, and two forensic examiners were prepared to make the first incision.

*Ding!*

"Basic Task: Complete the fingerprint extraction of the water-soaked corpse and confirm the identity of the deceased."

After accepting the task, Lu Chuan prepared to lift the fingerprints.

Judging by the body's form, the figure was well-proportioned, the legs were long, and the skin was fair.

Although the face was no longer clearly recognizable due to being gnawed on by fish, the oval shape of the face could still be discerned.

With hair reaching the waist, the person appeared to be under thirty; she was likely a very beautiful woman in life.

Lu Chuan did not use oil printing to lift the fingerprints directly. A body that has been submerged will suffer from swelling.

If not treated, the gaps between the fingerprint ridges would appear enlarged when lifted.

It would be like magnifying the entire fingerprint by a certain factor, which would cause significant difficulties during later comparisons.

Opening his forensic kit, Lu Chuan began to process the fingers of the corpse.

But before that, Lu Chuan needed to communicate with the forensic examiner.

After all, the forensic technician only has the responsibility and right to examine the surface of the body; to directly touch the corpse, one must obtain the consent of the forensic medical examiner.

"Forensic Examiner Wang, the fingers are swollen from immersion. I need to perform some processing on them, but it won't affect the completion of the autopsy. What do you think...?"

Wang Changjiang was a senior forensic examiner in the Criminal Investigation Detachment. In terms of skill, his technical level was comparable to Liu Guodong's.

However, in terms of status, he was not as high as Liu Guodong.

Action teams and criminal police squads generally do not rely on forensic examiners.

In the entire Criminal Investigation Detachment, forensic examiners are arguably one of the most relaxed positions.

They are on par with the lady at the newspaper stand by the entrance.

"It's fine," Wang Changjiang waved his hand. "There are no other wounds on the surface of the body; the cause of death should be mechanical asphyxiation."

"Xiao Shen, help Xiao Lu. First, take photos of the body to document its state before the autopsy, then let Xiao Lu collect the fingerprints."

"Yes, Teacher."

The voice was sweet and crisp, and the woman's smile was also very attractive.

She was Shen Yan, one of the "Police Flowers" of the Criminal Investigation Detachment.

She was Lu Chuan's senior, having joined the force two years ago.

The two had known each other since their university days; after all, one was a famous campus beauty and the other a famous campus heartthrob, so their paths were bound to cross.

"Sorry to trouble you, Senior. I'll treat you to dinner another day."

"Sure, which day exactly? I'll be waiting for you."

Shen Yan's smile was very sweet, bringing a touch of vitality to the eerie autopsy room.

"Let's make it tomorrow. Our respective departments should not be too busy tomorrow."

The condition of the corpse was simple, so the autopsy could be completed today, and the forensic work would be mostly done as well.

Tomorrow would be perfect for dinner.

Shen Yan finished the photography quickly, and then it was Lu Chuan's turn.

Opening his forensic kit, Lu Chuan took out a five-centimeter-long steel needle.

He then prepared a paper cup and slowly inserted the steel needle into the crevices of the corpse's fingernails.

The depth was shallow, only about one centimeter.

Shen Yan and Wang Changjiang had seen Liu Guodong and others collect fingerprints from corpses before, but they usually just washed the fingers and proceeded directly to lifting them.

It was never as complex as Lu Chuan's method.

"Lu Chuan, what are you doing...?"

Wang Changjiang remained composed, and though curious, he did not speak. The sensible Shen Yan stared with wide, curious eyes.

"This steel needle is hollow. It can, to some extent, drain the bodily fluids from under the nails and reduce the swelling, making the collected fingerprints easier to compare."

As he spoke, a pale yellow liquid began to drip from the end of the needle, and the pads of the fingers gradually shriveled.

Shen Yan watched Lu Chuan's operation with a look of wonder, occasionally offering words of praise.

Lu Chuan's mood was also quite pleasant; it was much like a peacock spreading its tail.

Collecting the fingerprints was that magnificent tail.

Lu Chuan finished his operation quickly, then collected hair and nail clippings to be used as DNA samples.

Next, Shen Yan and Wang Changjiang busied themselves with the autopsy and issuing the autopsy report.

Lu Chuan returned to the laboratory and first used instruments to extract the DNA information.

The extraction of DNA information is not like what most people imagine—simply putting a sample into a machine and receiving DNA data.

All DNA samples must undergo pre-treatment before information can be extracted.

In forensic terminology, this is called purification.

In the past, the Criminal Investigation Detachment used many different methods for DNA extraction.

They were mainly divided into two categories: liquid extraction and solid extraction.

However, ten years ago, the authorities developed reagents for the extraction and purification of DNA, which unified the methods used in criminal investigations.

This also greatly reduced the difficulty of DNA information extraction.

Lu Chuan had studied this in university, and over the past month, he had also watched Liu Guodong and the others operate the instruments.

Although he couldn't handle the most complex cases, standard DNA extraction was no problem.

After processing the samples, Lu Chuan began preparing for the fingerprint comparison.

The fingerprint database of the Haizhou Municipal Public Security Bureau is networked with the entire province.

This was a major project heavily promoted by the Provincial Department over the past few years.

With technological progress and the refinement of resident information, more and more people were having their fingerprints collected.

In some police stations, there were even quotas regarding how many fingerprints had to be collected per year.

Consequently, many people visiting police stations to handle affairs would frequently encounter a requirement to have their fingerprints collected first.

Although Lu Chuan did not possess advanced fingerprint analysis and comparison skills, his fingerprint collection was extremely standardized.

The system could perform the comparison automatically.

While Lu Chuan was busy, the salvage team at the Xingfu Reservoir site also achieved results.