Chapter 168: Real Case

The Qinghe Bureau's small lecture hall was located on the first floor of the office building.

The green plants inside were a bit withered, but no one cared.

It, along with other unimportant departments, kept its doors open, welcoming guests from all directions. This included members of the public who didn't know the truth, as well as police officers from various places who didn't know the truth.

However, the utilization rate of the small lecture hall was still very high.

As an administrative bureau that was formalistic, the Qinghe Bureau attached great importance to the organization and reporting of various activities. Otherwise, its existence would be too meaningless.

Today, the small lecture hall was also sitting with quite a few people, and then a tall young man was lecturing slowly, as if he were a college student giving a speech on stage.

It was just that the atmosphere was quite different.

The young police officer wore gray shoulder straps, which meant he was a technical police officer. Wearing a full set of police uniforms, he looked very good. Although he didn't look like the currently popular traffic-star types, he could be considered a gentle and sunny big boy, and with the bonus of the uniform, sitting in the lecturer's seat, with a serious expression, waving freely, it seemed like he could be used for publicity just by taking a random photo.

Jiang Yuan also wore a pair of non-prescription glasses for this training. He wasn't actually nearsighted, but he looked young, and his master said wearing glasses would be better.

And the group of police officers sitting in the viewing seats looked nervous and solemn, looking at the projection screen, their cheek muscles clearly twitching slightly, and their eyes were wide open, very forcefully.

The 20 approximate fingerprints matched in the first pass were listed on the right side of the screen in a vertical row.

The three-quarters on the left displayed the one with the highest value among the approximate fingerprints completely.

"Um, let's look at the fingerprints returned in the first pass."

Jiang Yuan pushed his unfamiliar glasses frame with one hand, grabbed the mouse with the other, clicked, and enlarged the fingerprint on the left to the full screen.

And the fingerprint displayed synchronously on the projection screen was also relatively clear.

"Um, there is an exclusion point here." Jiang Yuan clicked twice, enlarged the fingerprint again, and then his mouse drew a small circle on the right side of the fingerprint to show everyone.

For fingerprints that have already been matched, the standard executed is not how many feature points are consistent, but whether there are any inconsistent feature points.

This is easy to understand. If two fingerprints are the same, then theoretically, all their feature points should be the same.

Therefore, if two fingerprints have one inconsistent feature point, it can be determined as "excluded."

That is to say, the two fingerprints are not the same; they are not the same fingerprint.

Following this train of thought, Jiang Yuan eliminated two approximate fingerprints in a row.

At this time, Cao Keyang of the Qinghe City Bureau, who was sitting in the front row below, said: "Teacher Jiang, shouldn't we put the two fingerprints out for comparison? Excluding them directly like this makes it unclear for everyone to see."

Jiang Yuan reacted quickly, immediately clicked twice, and let the original fingerprint and the matched fingerprint appear on the left three-quarters of the screen at the same time.

"Sorry, I was thinking that the first few fingerprints could be done faster." Jiang Yuan said sincerely.

A hint of sourness inexplicably rose in Cao Keyang's heart, and he hurriedly said: "It's fine, this isn't your problem. It's just to say, we are lecturing, it's better to lecture a bit slower and clearer."

"Mm, I'll pay attention." Jiang Yuan nodded and said again: "Then let's re-exclude the first two fingerprints."

Then, Jiang Yuan used the exact same action to draw a circle on the right.

What was different was that he subsequently drew a circle on the left as well.

Thus, the audience below finally let out a continuous sound of "Oh."

Seeing this, Jiang Yuan pressed on, circled the second fingerprint and the third fingerprint, and then persuaded them to quit.

The "Oh, oh" sounds from the audience gradually decreased.

Technicians with a fingerprint level lower than LV1 began to feel a sour sensation in their hearts—a sour, astringent feeling that couldn't be described.

They finally understood that Jiang Yuan had actually memorized the original difficult fingerprint entirely.

So, the exclusion method just now was purely based on memory.

Then there was no need for comparison; having the original image in his mind made excluding or comparing naturally very fast.

This actually meant nothing.

If they had started preparing for the lecture a few days ago, everyone could have memorized the fingerprint... partially.

The key is, who would do that?

Such dense fingerprints, no one would expect them to be memorized, right?

The fingerprints themselves would feel annoyed, right?

There are trace examiners who have been paying attention to a certain difficult fingerprint for years and will gradually remember the features of that fingerprint, but the thing is...

During the time some people were letting their imaginations run wild, Jiang Yuan had already excluded three more approximate fingerprints.

Then, they heard Jiang Yuan say: "At this time, it is generally recommended to look at all 20 fingerprints. But we won't look at them today, because the similarity of the fingerprints coming out is getting lower and lower, which means the probability of matching later is already very low..."

Cao Keyang was stunned.

The crowd was stunned.

This feeling, why was it so familiar?

It was as if, when they were still in school, they lowered their heads to pick up a pencil, and when they raised their heads again, they couldn't understand what the teacher was saying.

Even the language at the last moment was the same: I won't write the subsequent steps, because they are relatively simple, so we'll skip them, but the conclusion that can be drawn from this is...

Jiang Yuan didn't intend to pause.

After the first wave of fingerprint screening, Jiang Yuan pulled out the original fingerprint again and said: "We are now marking the feature points for the second pass."

Dazzling,

Flowers confusing the eyes,

Eyes not seeing, heart not annoyed,

Annoyance is useless

After the operation, Jiang Yuan completed the marking of thirteen marking points again.

Jiang Yuan said: "The positions we just marked are relatively common marking points. They didn't match, which shows that the previous trace examiner did a decent job on the basic work, and the criminal suspect didn't leave a very clear full fingerprint for us to match. It doesn't matter, let's try again."

Similar to the previous steps, Jiang Yuan threw the marked fingerprint into the fingerprint database for comparison.

In a while, the data returned by the fingerprint database was another vertical row of 20 fingerprints.

"Still need to compare left and right, right?" Jiang Yuan asked Cao Keyang this time, showing politeness.

Cao Keyang nodded obediently and looked at the projector with concentration.

This time, he felt he should be ready.

On the left three-quarters of the projector, two fingerprints were listed.

Jiang Yuan's mouse moved lightly, drew a small circle on the left, drew a small circle on the right, and said: "Excluded, right? Same meaning as just now."

"The second one is also excluded."

"Same, huh."

"For the ones below, we don't need to circle them one by one, right?"

Jiang Yuan spoke while quickly flipping through the fingerprints.

He pressed the space bar on the keyboard, and a new fingerprint would appear on the screen, replacing the old one.

Since Jiang Yuan didn't need to circle them anymore, he just took one look, said "No," and then pressed the space bar again to replace it with a new one.

Cao Keyang started by staring at it, but soon fell back into the state just now:

Eyes

Messy

Eyes

Annoyed

For a moment, Cao Keyang almost thought he was watching short videos.

The internet celebrity young ladies all over the screen looked quite similar.

Take a look, swipe away.

Look at another one, swipe away again.

In a daze, half an hour passed.

At this time, Jiang Yuan also re-marked the feature points of the fourth wave and said: "Actually, the feature points we just marked weren't very necessary; it was just to show everyone."

"In the future, when you have the opportunity and practice until you are proficient, you can omit the marking mode just now, because the feature points marked just now overlap with the previous two times. If it's just for the sake of trying, doing it this way is not efficient."

"A more efficient way is actually to delineate a small area and then mark as many feature points as possible. This way, the accuracy of the feedback fingerprint will also be improved. Of course, the difficulty will also be higher."

"Still the same method as just now..."

While Jiang Yuan was talking, the sound of clapping the space bar came from the lecture hall.

Not only Cao Keyang, but most of the technicians in the lecture hall were a bit numb.

Jiang Yuan was doing it too fast.

Everyone couldn't keep up.

They didn't think that if Jiang Yuan followed their speed and did fingerprints while explaining, wouldn't a difficult fingerprint take several days to do?

The time for a training class was only two sessions of 4 hours in total.

An older trace examiner let out a clear cough at this time, which was about wanting to speak.

Everyone held their breath and stared, waiting for this brave big brother to speak for everyone.

After all, it was training in a disciplined force. If the teacher was annoyed, it would be easy to get into trouble.

The sound of clapping suddenly stopped.

For about half a minute, Jiang Yuan didn't speak or move.

The lecture hall was so quiet that Cao Keyang, who had already given up a bit, couldn't help but look up at the projection screen.

On the projection screen, there were still two fingerprints.

On the left was an original fingerprint, with the identity of a difficult fingerprint, just like a young lady wearing tight pants, looking like she was barely covered, yet revealing nothing.

On the right was a fingerprint from the fingerprint database, ordinary, just like an ice-cold imperial sister wearing a professional suit, with sharp eyes, refusing, and not a single flaw on her body...

"Matched, right." Jiang Yuan added a sentence later, which counted as part of the lecture.

Cao Keyang was stunned. What did "matched" mean?

He looked at the original fingerprint on the left, and then at the fingerprint from the database on the right.

It seemed quite similar.

Almost identical.

No flaws.

Cannot be excluded.

Then... wouldn't it have to be identified as the same?

In the end, the tight-pants beauty and the ice-cold imperial sister were the same person?

Cao Keyang was stunned.

It wasn't just Cao Keyang; half of the police officers receiving training were in a daze.

At this time, Jiang Yuan began to skillfully write the "same identification" appraisal report and applied for review.

A room of forty-something people just watched Jiang Yuan filling out the form alone.

Everyone understood the part about filling out the form.

"Wait a moment for the review on this side; I'll find the phone number of the jurisdiction here." While speaking, Jiang Yuan said to the students: "Sorry, I'm delaying everyone for two minutes. After all, the criminal suspect has been locked onto, so it's polite to make a phone call."

"It's fine, it's fine." A group of police officers waved their hands uneasily.

Jiang Yuan then switched back to the case details, found the information of the jurisdiction's police station, and laughed: "It's Miaohe County. I talked to them on the phone before. Wait a moment."

Jiang Yuan had matched a fingerprint of a cold homicide case in Miaohe County during the province-wide fingerprint battle, so he had the phone number of the Criminal Police Brigade Captain of Miaohe County.

Jiang Yuan dialed a phone call, and soon, he heard the laughing voice of the Criminal Police Brigade Captain of Miaohe County: "Forensic Doctor Jiang, how do you have time to call me? Is it good news?"

"I just matched an ordinary case, a robbery case from more than six years ago... Yes, I will send the specific information to you on the internal network. Yes, yes, oh... the review has passed... You're welcome, you're welcome."

Jiang Yuan was sitting in the lecturer's seat, the reception was good, and the conversation between the two on their mobile phones fell into everyone's ears almost completely.

The technicians present were all in a trance.

The temper of the Criminal Police Brigade Captain of Miaohe County was actually so good?

Can someone with such a good temper be a Criminal Police Brigade Captain?

Besides, what just happened?

In the eerie silence, Jiang Yuan completed the step of sending information on the internal network.

"Alright, the review has passed, so this cold robbery case from six years ago can be considered to have a new key clue. Next, it depends on whether Miaohe County can locate and arrest the criminal suspect. For us, the fingerprint comparison work for the case just now is considered finished."

Jiang Yuan clicked off the several pages he had just opened, which was considered completing the final finishing work.

"Let's find another typical fingerprint and repeat the method just now to see if it's feasible." Jiang Yuan searched for fingerprints again.

The guy who was clearing his throat just now finally couldn't help it, stood up with a "whoosh," but what he wanted to say had completely changed: "Just now, was that a real case?"

"Yes." Jiang Yuan responded and said again: "So it's a practical combat-oriented lecture. That... the content I said, the style of my lecture, can you get used to it?"

"Yes, yes, yes, but, no, we... no, you... no, you just solved a robbery case?" The guy clearing his throat was probably unable to accept this matter.

Soon, the small lecture hall was already buzzing with noise.

Someone even quietly sent a message: Brother, come quickly to see a god. ===== CHAPTER 169 =====