National Forensic Doctor
Chapter 280 - 280 259 Please Help_2

280: Chapter 259 Please Help_2 280: Chapter 259 Please Help_2 Jiang Yuan said a bit embarrassedly, “Okay.”

“All right, turn on speakerphone,” Huang Qiangmin said.

So Jiang Yuan took down his phone and switched on the speaker.

Huang Qiangmin’s voice came through, “Jiang Yuan, do a good job on the task assigned by Director Wan.

You still have two days off, but let’s skip them for now and consider you back at work.

Once you are done, you can take your leave.

Changyang City Criminal Science Center has also helped us with quite a few cases in the past.

This opportunity for cooperation is something to cherish…”

“Yes,” Jiang Yuan replied, following the etiquette strictly.

“Director Wan, I’m entrusting Jiang Yuan to you.

He’s young and may not know much yet, so please be patient with him.

If there’s any issue, just let me know and I’ll reprimand him,” Huang Qiangmin finished his nagging and ended the call.

Wan Baoming put away his phone and sighed, “Your Captain Huang, he’s not as easy to talk to as he used to be.”

Jiang Yuan just smiled and didn’t make a sound.

Borrowing someone else’s great ox to plow the field is probably not the same as borrowing a cat to catch mice.

With a few clicks, the computer whirred to life.

When it comes to image rendering, no matter how high-end the computer is, the noise it makes is the same.

That’s like you know, right?

“Director Wan, is it convenient to discuss the case?” Jiang Yuan took the opportunity to ask Wan Baoming.

“This is a case from last year at the Maixin Electronics Factory.

A female worker was pushed from the rooftop.

Initially, it was thought to be suicide, but later, an eyewitness claimed to have seen two people on the rooftop, and there was a pushing motion…” Wan Baoming described the scene and then focused on the evidence:

“The initial police response was somewhat problematic.

Because it was first suspected to be a suicide, the crime scene preservation was not ideal.

Factory security and workers have all been up on the roof.”

“Secondly, there’s only an eyewitness account, lacking surveillance footage.

Since everyone wore uniforms, it’s challenging to identify the murderer.”

“The third issue is that factory workers don’t know each other well.

The Maixin Factory hired people on a temporary basis, recruiting new workers for large orders.

When an order was nearly completed, those workers would be let go, and new ones would be recruited for the next big project.

Hence, solving the case by tracing through social connections isn’t easy either.”

As Jiang Yuan listened to Wan Baoming’s briefing, he couldn’t help but ask, “So the only evidence is the fingerprint on the clothing?”

Wan Baoming sighed, “The problem now is that the fingerprint on the clothes has become contrary evidence.

Several suspects the detectives focused on have been excluded by the fingerprint evidence found on the clothes…”

Jiang Yuan laughed lightly at this and then asked, “All the factory employees would have been fingerprinted, right?”

“Yes.

After the incident, the factory was shut down immediately, and the video surveillance of the entrances and exits was intact.”

Jiang Yuan nodded in understanding; with this, the fingerprint database issue was essentially solved.

From the perspective of a trace evidence technician, this was an excellent environment for fingerprint comparison.

As long as a fingerprint could be produced, it could be matched.

Reflecting on this, Jiang Yuan frowned and said, “So the core of the problem is matching fingerprints.

With last year’s case being unresolved, matching them one by one should suffice, right?”

Wan Baoming couldn’t help but smile and quickly covered it, saying, “When I mentioned that the factory is the Maixin’s, you probably didn’t understand the scale.

At that time, the factory had received a large order and was operating at full capacity, with nearly 30,000 workers on site.”

Jiang Yuan then understood.

In a large factory with tens of thousands of people, it was certainly impractical to compare fingerprints one by one, especially when the quality of the fingerprint was so poor.

“What method did you use for lifting fingerprints?

Cyanoacrylate?” Jiang Yuan asked, observing the fingerprint and gradually getting into the state of mind for comparison.

Understanding Jiang Yuan’s implicit meaning, Wan Baoming gave a wry smile, “Yes, it was developed with cyanoacrylate fuming.”

Similar to ninhydrin fuming, the cyanoacrylate fuming method also involves applying a chemical agent to reveal latent sweat prints.

Similarly, all these methods have an aspect rarely discussed—flaws can easily occur during the process.

If a criminal unintentionally leaves behind a fingerprint, and that print is then damaged or not fully revealed, there’s no chance they will provide a second one.

Like this fingerprint here, so poorly scraped, trace evidence technicians still have to painstakingly match it.

Usually, the blame falls on the technicians who collected the fingerprints—more often than not, crime scene investigators are criticized.

Jiang Yuan adjusted the fingerprint slightly using image software and gradually formulated a plan.

Feeling energized, he lost interest in chatting with Wan Baoming and said, “Why don’t you play with the dog for a while?

I’ll tell you once I have some results.”

“Okay,” Wan Baoming replied, then a moment later seemed to catch on, “Am I supposed to wait here?”

“Well…

if you’ve got other things to do, please go ahead,” Jiang Yuan casually replied.

Wan Baoming hurriedly said, “That’s not what I meant.

I was just wondering… uh, will there be results today?”

“Possibly.

Right now, the main task is image processing.

The fingerprint was taken from cotton clothing.

Cotton, as a natural fiber, is helically twisted, and its cross-section looks like a kidney bean.

It’s also prone to fuzz, which is the main reason for the lack of clarity in latent sweat prints,” Jiang Yuan briefly explained to Wan Baoming.

Wan Baoming watched Jiang Yuan, saying, “I’ve worked in trace evidence too.

I understand the principles, but…”