National Forensic Doctor
Chapter 481 - 481 442 The Nail

481: Chapter 442: The Nail 481: Chapter 442: The Nail Changyang City Criminal Science Center.

An independent small building surrounded by lush greenery, an office environment with a pleasant temperature…

A serious-faced group clustered around Jiang Yuan and the evidence “long nail.”

This was their most favorable piece of evidence obtained thus far.

Just like the bullet in a shooting case, the long nail in this case carried everyone’s hopes.

Besides that, the other pieces of evidence in the case were weak circumstantial evidence.

Surveillance videos, fingerprints, footprints recovered, or some cigarette butts and bloodstains gathered at the scene were merely self-consoling, without the power to point to the murderer.

Jiang Yuan, thinking from the perspective of the murderer, felt that a long-range weapon truly provided a significant advantage.

If it came to killing, using one’s hands made it easy for the victim to inflict injury, thereby leaving behind clues.

Knives were a bit better but, being close-combat weapons, they also carried the risk of the assailant being injured, and skills like Bloodstain Analysis were a major threat to bladed weapons.

Blunt weapons were similar, having their own pros and cons.

The main fear was not killing with a single strike, drastically increasing the risk.

Additionally, the insufficient deterrent effect of blunt weapons could significantly increase the victim’s chances of resisting.

The modified nail gun, as a long-range weapon, had very clear advantages.

It did not just minimize the chance of resistance, but also it killed quickly, leaving behind very few traces as physical evidence.

The disadvantage was that it left behind tangible evidence, like the long nail in front of them.

Wan Baoming introduced the situation, “This nail probably isn’t a model specially made for nail guns.

The modification done to the nail gun by the killer is quite peculiar.

The most common modifications performed on nail guns now are to make them shoot metal ball bearings, which have greater range and power.

His modification only allows for a maximum range of about two meters; however, its power remains significantly strong.”

“There are three common types of nail guns on the market: pneumatic, electromagnetic, and powder-actuated, with powder-actuated being the most common, also known as cartridge nail guns.

Originally, they were essentially nails with a section of blank cartridge attached to them, similar to weapon-grade blanks, hence called nail cartridges.

Now, we have no cartridge cases left behind, only the nails, and they are not even special nails, which is troubling…”

“In terms of shooting residue, physicochemical analysis and infrared spectral examinations have been conducted.

Trace evidence is still being processed, with no news yet.”

Jiang Yuan listened and simply nodded.

To speak of it, he had actually never seen a cartridge nail gun or nail cartridges before, but from the perspective of Tool Trace Identification, it was all the same.

And as he watched, it seemed like a random murder case.

The primary reliance for the person daring to undertake this was their Level 6 skill in Tool Trace Identification.

As the saying goes, a goose leaves traces as it passes by, let alone such a large industrial product…

“The nail is indeed a common model, but there is still a way to trace its source.” When Jiang Yuan came, he had already considered this issue and then said, “Can we buy the same model long nails sold on the market to compare?”

“There are many types and manufacturers of those nails.

There are more small factories that produce nails than those that produce ball bearings.” Wan Baoming was a bit surprised and said, “How about we wait for the trace evidence results from the nail cartridges to come out and follow that lead?”

“The killer modified the nails, it’s probably going to be hard to trace the nail cartridges.

But, let’s walk on two legs here and check both.” Jiang Yuan didn’t insist; his approach was admittedly more trouble, however, for a case of this level, it was totally normal to pursue two leads simultaneously.

Moreover, considering how meticulously careful the killer was, it was not going to be easy to track down the culprit based on such a conspicuous flaw as the nail cartridges.

“All the same model long nails sold on the market… Let me think of a way to buy a complete set.” Wan Baoming felt that if they could identify the source, it wouldn’t be a bad lead.

However, ordinary long nails were far too common.

Jiang Yuan then added, “We could purchase the same model long nails from each online shop for comparison.

Also, buy all the same model long nails sold in Changyang City’s markets and then compare them…”

Wan Baoming did not expect Jiang Yuan to come up with such a cumbersome method and said, “How long would the comparison take?

The key question is, can it even be discerned?”

“It can.

It won’t take too long; as long as we buy enough nails and have a comprehensive collection, we’re sure to find it.”

For Jiang Yuan, once he had the nails in hand, determining whether two nails were manufactured by the same company was simply a matter of a quick comparison.

Wan Baoming couldn’t grasp the strength of a Level 6 skill in Tool Trace Identification and was still frowning as he said, “Even if they were from the same company, they could be produced in different factories, and even the same factory might have different batches…”

“We’ll try to get as complete a set as possible.

If we start buying now, there’s still a good chance to find ones from the same batch.” Jiang Yuan wasn’t concerned about whether they were from the same batch, but if a factory had different production lines…

“Alright.” Wan Baoming could only agree.

“That’s all the leads we have for now; let’s give it a try.” Jiang Yuan wasn’t making any guarantees.

Coming up with a potential breakthrough path didn’t mean he had to take complete responsibility for it.

Wan Baoming naturally understood and, after deciding, first arranged for people to purchase nails from various platforms and markets.

Although it seemed unlikely they could buy every single same model long nail from the market, upon further consideration, it was highly improbable the killer would expect the police to make a breakthrough from this angle, at least he couldn’t produce long nails himself.

If he used steel balls—there would naturally be supply channels for steel balls, and it’s possible that some channels might be easier to investigate.

“At least it’s a lead.” Wan Baoming put down his phone, smiled at Jiang Yuan, and said, “Better than how aimlessly busy we’ve been these past few days.”

“What about that suspect, could he be the perpetrator?” Jiang Yuan couldn’t find such details in the case files, as they were not confirmable.

Since everyone present were their own officers, Wan Baoming slowly shook his head and said, “The suspect was identified based on a description given by a couple who were hiking, merely because the timing was close to the second incident, but we lack full human and material evidence.

Now with the third incident, it’s unlikely he’s involved.”

“Has the suspect been to prison before?”

“Yeah, he was previously jailed for violent debt collection.

Once released, P2P lending had all but died out, and he ended up unemployed.

We initially thought he was retaliating against society.”

Jiang Yuan hadn’t met the person and didn’t say much more but then requested to see the body.

The ultimate eyewitness in a murder case is always the body.

Jiang Yuan, being a forensic doctor, left examining the body last, hoping to accumulate some information first for a more targeted approach.

Wan Baoming had everything prepared and immediately took Jiang Yuan to the autopsy room.

After the two left, the technical police officers at the Criminal Science Center couldn’t help but discuss among themselves.

“Ningtai Jiangyuan, huh…

Looks like he also feels it’s a tough nut to crack.”

“He’s a forensic doctor.

Now that he’s looking at the body, he might find a new direction.”

“I heard that he went to Luyang City this time and cracked the case involving bodies buried by the highway, pulling out three people in one go.

He even pacified Miao He County, filling up the detention center.”

“Otherwise, how could Chief Yu help Ningtai County apply for a lab?

There are only a few slots in the entire province.

But this case is really hard to solve.”

“If it can’t be cracked, there will be trouble.

None of us will be sleeping, just waiting for the killer to strike a fourth time.”

The several brigades of the Changyang City Criminal Police Detachment are actually on high alert already.

Even if the case can’t be solved in a short time, they want to prevent a fourth or fifth occurrence.

The atmosphere domestically is quite different from abroad.

Police chiefs abroad who deal with serial killers can keep to themselves as long as they can take the criticism.

But domestically, if uncontrolled serial cases arise, angering the leaders, anything could happen.

Even the technicians at the Criminal Science Center have to worry about their own fate under the imminent thunderstorm.

There’s no time to sleep; in such cases, this may just be the beginning.

For a moment, everyone fell silent.

The Changyang City Criminal Science and Technology Center is also a significant investment for Shannan Province.

As the main force of the provincial capital’s crime lab, it actually has advantages in both funding and staff retention.

Over the years, the performance of the Changyang City Criminal Science Center has been quite satisfactory, depending on whom you compare it with.

However, this time, everyone hopes that Jiang Yuan will live up to his name.

This is the peculiarity of the policing profession—envy and jealousy are acceptable, but there must be someone who can shoulder the responsibilities.

Moreover, unlike other industries, where a mutual understanding of ‘you scratch my back, I scratch yours’ might exist, it’s almost impossible to have any such understanding between detectives and criminals.

Criminals would have to give up far too much; only in chaotic situations would they cooperate with the police.

For two days in a row, Jiang Yuan immersed himself in the quagmire of evidence.

The forensic autopsy did not yield any useful information.

It only clarified some medical history of the three elderly victims, which was evidently too late to be helpful now.

As for the nails ordered online, they were delivered continuously and piled up in bags.

Soon, the office assigned to Jiang Yuan was so filled it became unusable, and everyone began to store nails in the warehouse.

No one knew whether this approach would yield results, including Jiang Yuan himself.

The only difference was that while the other technicians saw this as a significant project, only Jiang Yuan felt it was easy.

Without the need for an auspicious day, once enough nails had been bought, Jiang Yuan first called Mu Zhiyang, then Wang Chuanxing and Tang Jia.

The four of them sat in the office, with two labeling, unpacking, and recording, one labeling and categorizing and responsible for filming, while Jiang Yuan sat at the table.

He examined the original evidence nail again and again, even under a magnifying lens, and then started to go through the purchased nails, one by one.

Whether two nails were manufactured by the same factory is somewhat distinguishable by the layman on cursory inspection.

For instance, the color may vary; some are yellow, some silver, some gray…

In addition, there can be subtle differences in exact shape and size.

Due to tolerances, nails of the same size 6.3*12 can seem thicker or thinner when compared.

However, this would only filter out some of the nails.

There would always be nails whose color, shape, and size were extremely similar; nearly indistinguishable to the naked eye.

According to the other technicians’ assumptions, to distinguish these nails further, you would need to use instruments for examination.

And proving something is far easier than proving its absence; even if an instrument proved that two nails shared an element, it would still be difficult to prove they came from the same source.

More complex instruments would be necessary.

Yet Jiang Yuan seemed unaffected by such concerns.

He sat in front of a clear desk with unexamined nails on his left and passed the nails to the right after inspection.

Completing a comparison was not only efficient but quiet as well.

It was only when Wang Chuanxing started transporting nails from the warehouse that the technicians from the Criminal Science Center began to realize that Jiang Yuan was not joking around, but had actually mastered a skill they didn’t quite understand.

“Are you really comparing the nails?

Can you tell the difference?” Wan Baoming rushed over upon hearing the news, looking at the temporary assembly line setup in Jiang Yuan’s office, he was somewhat speechless.

“So far, I’ve found three candidates.

I’ll know the final result after looking through the rest,” answered Jiang Yuan, not needing to explain anything else to Wan Baoming.

He then asked, “How are the results of the trace evidence analysis?

Can you determine the origin of the propellant?”

“It’s determined, but it’s not very useful,” Wan Baoming sighed.

“What do you mean?”

“The trace element analysis found a small amount of aluminum powder and gum arabic in the propellant residues.

In China, only three companies produce propellants, and the one used by the killer happens to come from Nanshan Company, the largest manufacturer.

They changed their process in ’86 and now produce 1.4 billion nail cartridges annually.

There’s no way to trace it further.”

Jiang Yuan nodded, knowing this was the expected outcome, and continued to focus on the nails.