Chapter 338: Command

"Human traffickers have always been mostly recidivists." Gao Changjiang frowned and answered Jiang Yuan's words, saying: "We have also screened all the human traffickers who have been released from prison recently. More than a dozen police officers are doing this, and currently, there is no discovery either."

Jiang Yuan straightened his waist, wanting to continue speaking.

Gao Changjiang felt that Jiang Yuan's understanding of the case was not enough, pretended not to see it, and continued: "Looking at the existing scenes, the traces left by the murderer are indeed very few. Precisely because of this, we requested the ministry to invite experts to assist..."

The several experts present looked at the case files and did not speak immediately.

Gao Changjiang let out a breath and said: "Although the traces are few, the support given to us by the superiors is extremely high. As long as there is a clue, we can continue to investigate..."

"Director Gao, we have already filtered out the valuable clues as much as possible since yesterday. By now, it is already very difficult to filter out reasonable clues." The expert sitting opposite Jiang Yuan topped Gao Changjiang back.

The difference between cases is huge. Some cases have perpetrators who don't know the trade and are not careful, so clues are everywhere. The main work of criminal police or experts is to find the easiest clue, and by the way, when catching the person, make the evidence chain complete.

But some cases have perpetrators who are really careful. Coupled with a little coincidence or luck, the traces left are very few.

In this situation, choosing the investigation direction becomes very important. Some investigation directions can catch people at the time, while some investigation directions are missed, and it is useless to find them later.

For cases like missing children, encountering the second situation is already very difficult.

Assuming one or more perpetrators take a child away using a relatively secretive method in a place without surveillance, as long as they are not stopped during this period, almost no traces will be left.

Especially in places like vegetable markets, people come and go, and traces like footprints or fingerprints can only be described as messy. Gao Changjiang wanted to use human wave tactics before, which was trying to filter out previous offenders from the vast number of fingerprints.

His thinking is actually not bad, but now people doing fingerprint comparison is actually not that fast. Maybe it will be better after applying AI technology in the future, but as of now, processing hundreds or thousands of fingerprints is still not very possible.

The most possible and most appropriate way is surveillance coming and going, but the problem is that now even the actual coming and going of the perpetrator cannot be found.

The clearest and most reliable clues the police have mastered are when the child was lost and where the child was lost. Apart from this, there is almost no confirmed information.

You don't use a bunch of uncertainties to infer a certainty; that difficulty is too high.

"I know, the case is very difficult, but we can't just wait like this." Gao Changjiang used a not-so-clever method to persuade everyone, saying: "I suggest we cooperate with Professor Liu to conduct a crime scene reconstruction, and at the same time, conduct a new combing of the case to see if there are any other clues..."

Professor Liu, who was named, frowned, but he really did not object.

Other experts also had similar expressions.

When technology is done to the depth, certainty is less and less. Making the possible out of the impossible is the daily routine of every expert present. If not for this, how could they be on the ministry's list?

Although the difficulty still exists, everyone indeed has the confidence to force a breakthrough.

Jiang Yuan had no choice but to follow the crowd to the Er'ma Lane vegetable market where the incident occurred.

Gao Changjiang had actually already blocked the vegetable market.

Therefore, he said he would start searching tomorrow morning, but the actual work had already been done in advance.

Expert Liu walked around the vegetable market twice to look at the scene.

Jiang Yuan also followed.

Crime scene reconstruction is a required item for every criminal science student. As for whether they can learn it well or learn it, there is no need to struggle too much. For the same skill, refer to advanced mathematics and discrete functions.

Expert Liu took a notebook and a pen, drawing while looking. Occasionally saying two sentences, the assistant beside him would take shorthand.

Jiang Yuan also mastered a little bit of crime scene reconstruction ability through bloodstain analysis, but looking at this kind of non-red scene, he was at most at the LV1.5 level, not showing cowardice, so he didn't speak and just followed along to look.

The LV4 crime scene investigation that Jiang Yuan had mastered early on could still exert a good advantage in such an environment.

Theoretically, if he could find the scene where the last child was lost, Jiang Yuan would at least have the ability to separate the vast majority of DNA at the scene, which would have a high probability of including the human trafficker.

However, comparison is still a big problem. Considering that a large number of fingerprints at the scene have already been compared, brushing another wave of DNA doesn't have much significance. If the perpetrator wore gloves or something, the probability of leaving DNA is also not high.

Bang!

Another ultra-bright dysprosium lamp was connected. This kind of lighting equipment often used on construction sites can illuminate a 1000-square-meter area when hung high. With multiple lamps hung continuously, the brightness inside the vegetable market is no lower than during the day.

This helps in finding fingerprints and small physical evidence, if any.

"How is it?" Gao Changjiang had also not slept for 30 hours, his eyes fighting each other from sleepiness.

Expert Liu shook his head: "When the perpetrator took the child away, there was no violent action. It is very likely to be something like abduction. The high probability is following the direction of the crowd. Among the several doors here, I think the possibility of the door on the west side is greater..."

Gao Changjiang was quite disappointed listening. If it were only to this extent, he could also say a bunch. Of course, it would be said more casually.

"We can't wait for the perpetrator to commit a crime again!" Gao Changjiang scolded angrily twice, very unhappily.

Many cases end up like this. Because the murderer cannot be found from the previous cases, one can only wait to see the later cases.

If the perpetrator stops for some reason, this case basically collapses.

"Find the previous old cases." Jiang Yuan looked at the vegetable market, which was the most important scene, and just became more certain of his thinking.

Gao Changjiang had no other choice, so he could only turn to Jiang Yuan and say: "We haven't matched any suitable old cases yet."

"Not necessarily in this province. He always needs practice to reach the current maturity. And the sales channels. If there were no sales channels, there would be no need to abduct 4 children at once." Jiang Yuan had done so many cases now, and he had an increasing understanding of the levels of criminals.

Gao Changjiang pondered for a moment and said: "Then what means should be used to find these old cases?"

He was not unable to hear Jiang Yuan's suggestion, but Jiang Yuan's suggestion obviously deviated from his investigation range.

Jiang Yuan was actually not too sure, but after solving so many cases, his self-confidence had long since risen, and he said very naturally: "First comb these cases out, and then look for similarities."

The workload of this work is naturally not small, but Gao Changjiang is not lacking people now.

He just said with some regret: "I originally hoped to use technical means to quickly solve this case."

"The process of combing cases will definitely use everyone's technology." Jiang Yuan said whatever he had to say. Anyway, he was in a strange city in the neighboring province. He didn't mix under Gao Changjiang, nor was he sold to Gao Changjiang, so his confidence was sufficient by eighty percent.

Gao Changjiang looked at other experts. Seeing that everyone had no opinion, he nodded simply: "Then go back and comb the cases. What is needed?"

"Find some experienced police officers and find all the disappearance cases and abduction cases in this province and the surrounding areas in the last two years." Jiang Yuan felt a bit like he had taken over the investigation.

This is also a habit that has formed. His status was high when he was in Ning County. After being sold to Changyang City, he had a separate cold case special class to do things, basically forming the habit of command and order.

In contrast, other experts, although long-established, because their technology was single and it took many years to accumulate technical advantages, they tended to do technical support rather than command investigation.

Gao Changjiang hesitated, but still did as Jiang Yuan said. It was originally an investigation plan just determined, plus the name of the expert sent by the ministry—although he was the director of the municipal bureau, Gao Changjiang had actually not done many ministry-supervised cases.

Thus, everyone turned back, and at the same time deployed personnel, starting to screen cases overnight.

The 8 people Jiang Yuan brought were more familiar with this mode, and then began to help each other, as if they had formed small groups, the kind commanded by Jiang Yuan. ===== CHAPTER 339 =====