Chapter 168: Take a Look at the Case

A tall criminal policeman sneaked in through the back door.

The small lecture hall of Qinghe Bureau is one and a half stories high, and the back door has to go through a special fire escape. Not many people are willing to go through it on weekdays.

But today, in order to get in during class, and because they were embarrassed to come in in front of everyone, many people chose to go through the back door.

There were about twenty people.

Counting them all, it was almost the manpower of a squadron.

If so many people illegally went through the back door, it would take a whole squadron to catch them all.

At this moment, the one who was going through the back door was Chen Wenming, the leader of the Trace Inspection Group of the Criminal Science Institute of Qinghe Bureau. He also received a text message from Cao Keyang, so he couldn't help but come to take a look.

Qinghe Bureau does not handle cases itself. The Criminal Police Brigade under its jurisdiction usually does the most to guide the Criminal Police Teams in various places, count various indicators and figures in various places, formulate various work requirements, serve the grassroots, and pass on information, etc. In this environment, the role of the criminal science unit is more likely to be highlighted.

For example, the criminal science brigade that was supposed to be set up in Qinghe Bureau was transformed into a more professional criminal science institute, and the trace inspection team also rose.

Some county bureaus could not do or did not do well in technical inspections, so they sent them to the county bureau criminal science center. For example, Ningtai County did not have its own document inspection, and in terms of trace inspection, the ability of tool inspection was also very weak, and the ability of firearms trace inspection was basically non-existent.

Footprint inspection was also lacking. At least in the past, Ningtai County's footprint inspection was also sent to Qinghe Bureau.

Chen Wenming is the footprint inspector of Qinghe Bureau and a famous footprint expert in the province.

Previously, the footprint expert Chen Wenming made a mistake in the height of Jiang Yuan's footprint case. And Chen Wenming naturally heard about this.

This made him subconsciously avoid Jiang Yuan's training class.

It was not until the story of Jiang Yuan's "actual combat" fingerprinting on the scene came that Chen Wenming ran over to watch the battle.

He is a famous footprint expert in the Municipal Bureau, but as a trace inspection technician, he can also do fingerprints. Moreover, Chen Wenming's fingerprints are also quite good, but they are not good enough to participate in the provincial fingerprint battle.

Because of this, Chen Wenming always feels that Jiang Yuan's "practical class" is a bit too gimmicky. Chen Wenming stretched his head and looked down, and saw that Jiang Yuan was looking at the screen without even glancing at him. There are about fifty or sixty people sitting in the small lecture hall with 170 to 80 seats. A small half of them do not need to attend the training course.

Chen Wenming curled his lips, then found the position of Cao Keyang in the same group and groped over.

After a break, Cao Keyang had retreated to the middle position, but his eyes were still a little blurred, and his mood was still a little sad. Emo was too lazy to serve Jiang Yuan.

"How is it?" Chen Wenming sat next to Cao Keyang and asked in a low voice. Cao Keyang laughed twice and said, "Now we are marking the fifth feature point." "So we marked it four times and it didn't match?" Chen Wenming couldn't help but laugh.

Marking four feature points is not a lot. Generally, if the fingerprints collected at the scene don't match, they will at least mark it three or four times, or four or five times, before giving up.

If it is an important murder case, it is normal to mark it more than ten times or twenty times.

The number of times for backlog cases is even higher. Most of the fingerprints for trace inspections are tested. This is the most normal practice.

But psychologically speaking, if it still doesn't match after marking four times, it feels that the probability of matching again is not high.

Instead, Cao Keyang spoke for Jiang Yuan, saying, "Because we chose the difficult fingerprint, it's not normal that we matched the fingerprints after four marks in the previous class."

"Normally, fingerprints won't be matched like this on the spot." Chen Wenming frowned and said, "Fingerprint matching itself is somewhat accidental."

Cao Keyang nodded immediately, "Yes, I think so too."

"It's common for fingerprints to fail to match. No matter how good the fingerprints are, what can you do if there is no corresponding fingerprint in the library?" Chen Wenming sighed.

"Yes, yes." Cao Keyang agreed.

"This kind of on-site fingerprint comparison can easily give people a bad impression, as if fingerprint identification is something that can produce results in minutes." Chen Wenming sighed again and thought to himself that if it weren't for the last footprint incident, he would have to talk about it.

However, it was precisely because Jiang Yuan's footprint identification overturned Chen Wenming's own footprint identification not long ago, and thus solved a murder case. Chen Wenming felt that it was difficult for him to come forward to educate Jiang Yuan.

Educating him now would make him look intolerant.

Chen Wenming then looked at the screen, with a little regret and pity, and a hint of helplessness and fatigue.

It is easy for young people to go astray in the honor and applause. This is nothing. People always have to go through something to grow up...

"I didn't match it this time either." Jiang Yuan's voice came from the podium. Chen Wenming pursed his lips unconsciously.

It was expected.

No matter how powerful the fingerprint expert is, the probability of matching the fingerprint is not high. This can be seen from the fingerprints of suspects that are constantly accumulated in the fingerprint database. If the fingerprints are so easy to match, there would be no fingerprints in the fingerprint database long ago.

Nowadays, criminals who are slightly smarter know how to hide fingerprints.

The era of bloody fingerprints everywhere, like thirty or forty years ago, has long ended.

Of course, the devil is one foot high and the road is ten feet high. The fingerprint extraction technology is also constantly improving.

Technologies such as extracting fingerprints from plastics and fingerprints from fabrics are now very mature. However, the fingerprint conditions extracted from these places are not much better.

If you want to match these fingerprints, the difficulty has increased no matter how many times.

Therefore, no matter which angle he analyzes it from, Chen Wenming does not think that "practical" lectures are an option. At this time, Jiang Yuan's voice came again: "Let's mark the feature points again."

Chen Wenming then adjusted his seat and prepared to take a good look.

Then, Jiang Yuandao said: "Marking feature points, especially marking feature points multiple times, we must learn from previous markings. So what have we learned from previous marking of feature points?"

Chen Wenming was stunned for a moment, and he couldn't help but feel surprised: Can you still think like this?

Jiang Yuan continued in a teaching tone, saying: "Look at the several feature point markings I made before, it is easy to see that the middle part has been marked in the many feature point markings, because here The conditions are relatively good and it’s easy to find feature points, right?”

Some people in the venue nodded cooperatively.

Jiang Yuan said again: "If it is an ordinary fingerprint, there will be no problem with our previous marking mode. It must be marked well. However, we have failed to mark many times now. I think we need to reconsider the characteristic points. range of markings.”

Jiang Yuan used his mouse to draw a circle on the fingerprint and said, "We have marked the characteristic points here many times before, and the matched fingerprint conditions are also average. So this time, we will not mark the characteristic points in the circle. ”

"It's a little difficult. In this case, the difficulty will be increased a lot, but from my understanding, increasing the difficulty is actually a prerequisite for winning the fingerprint. Curry's difficult fingerprint, the more difficult it is, the easier it will be. Comparison."

The principles explained by Jiang Yuan have little impact on newcomers to trace inspection.

Half of the people here usually focus on collecting fingerprints, and have never compared fingerprints in the fingerprint library. Now that it is easier to compare with the difficulty, and the inner meaning of it, it is somewhat beyond the scope of understanding.

Chen Wenming listened immediately.

His fingerprint level is not very high, but his footprint identification level is indeed top-notch in the province. In his daily work, Chen Wenming has actually discovered this truth long ago.

The footprints involved in the backlog of cases, especially the footprints involved in major and important cases, are simpler and more routine, and the more difficult they are to match.

If you think about it carefully, if such footprints can be compared, why did the previous trace inspection leave the footprints until now. It has to be a difficult footprint, which is easier to hit.

Especially for tracks that are beyond the range of most people, once the entry point is found, the probability of hitting is ridiculously high. From a certain perspective, this is equivalent to coming up with new technology.

New technologies are used to combat criminals, resulting in an "easier to hit" situation. Chen Wenming nodded slightly again.

It is true that in a footprint appraisal, people who accidentally defeat themselves can really sum up something. As for specific abilities...

"This time the difficulty is relatively high, so I marked it first because the method used is quite special and not very reference..." Jiang Yuan's voice was slightly soothing, but he still operated while talking.

Chen Wenming stared at it for a while and found that it was a very special method—because he had never seen it before. Chen Wenming couldn't help but ponder.

His level is still different from other trace inspections below, so he naturally does not belong to the group that Jiang Yuan said is too difficult.

However, before Chen Wenming could figure it out, Jiang Yuan had already marked a dozen characteristic points along the way.

"Let's run it again and take a look." Jiang Yuan completed the mark and threw it into the software. He even had time to take a sip of tea.

Chen Wenming frowned and looked, and saw 20 similar fingerprints popping up. Jiang Yuan still watched at a fast speed.

It didn't take much time to look at a dozen fingerprints in a row.

Chen Wenming is already a little impatient. It can be said that giving lectures like this is not attractive at all.

He turned his head and looked behind him, but unexpectedly discovered that a group of guys who usually didn't take part in training seriously were actually looking at it very seriously at this time.

Chen Wenming was thinking, since when did trace inspection become a spectacle? Even if it attracts everyone's attention, how can it last...

"We won the competition." Jiang Yuan's clicking sound stopped at some point. Chen Wenming quickly raised his head.

Jiang Yuan added: "This is another fingerprint connected to a backlogged case. Well, these two fingerprints should be identified as the same, and then the case can be handled together."

Merger means the possibility of bringing more clues. For the detection of the case, it is always beneficial. Then, Jiang Yuan began to fill in the appraisal report with the same certification.

Some policemen were already shouting from below: "Look at the case."

"Call."

Jiang Yuan also had a smile on his face. He waved his hand at the lecture table and said, "Don't make the call right now." After writing the appraisal report, he opened the case.

One was a burglary and the other was a burglary. Chen Wenming's eyelids suddenly twitched.

These two cases are quite heavyweight.

Jiang Yuan also looked at it carefully for a while, and then said: "The two cases are quite serious, so let's do it differently."

So, Jiang Yuan used Photoshop.