civil forensic

Chapter 902: Clue Direction
The four bodies were exposed outdoors, so there were traces of varying depths around the crime scene, including those of the suspect and the murderer. In theory, there were also traces of rape and even necrophilia.

However, due to the decomposition of corpses, the unusually rapid growth of local vegetation, and the frequent heavy rains and scorching sun, these traces have been disturbed to a great extent.

Just by looking at the footprints collected from the four cases, we can roughly judge that only the murderer and the victim were present at the crime scene. However, it is extremely difficult to obtain more clues through positive analysis.

However, on the other hand, with certain analytical conclusions, it is sufficient to use these traces to make arguments.

Jiang Yuan watched the autopsy videos of the three bodies and gave a positive answer to the second and third bodies: "Both bodies also showed signs of being raped."

"Is it that only the first corpse was not raped?" Nicha pondered for a moment and said, "Is it because he didn't have such a strong desire the first time? Or is it that he didn't know that he had such a desire? Or is it that his psychology gradually became abnormal?"

Malaysia was once a British colony, and the police's configuration, training, and crime-solving models are all copied from the British and localized. So, when faced with a serial killer, Nizar's first move was to conduct criminal psychology analysis.

Jiang Yuan did not put himself in the murderer's shoes and think from his perspective. He just raised his head and said, "The first body was more decomposed, so we can't be sure whether it was raped. In addition, it is possible that the rape was unsuccessful. In this case, it would not be reflected on the body."

Nicha suddenly realized: "Yes, it may be his first time to rape a corpse, so he is not very experienced and may not be able to get in."

"It's also possible that he was too excited and ejaculated prematurely outside. If you wipe it afterwards and leave it outdoors for another two days, the tissue outside won't be visible." Jacob put forward another point of view.

Nicha, Jiang Yuan and others all looked at Jacob with suspicious expressions, and Zhong Renlong's translation paused twice before continuing. Then, the comrades from Ningtai also looked at Jacob with "suspicious eyes".

Jacob said hurriedly, "Rapists often have problems with premature ejaculation and impotence. It's not strange that they ejaculate prematurely due to being too excited."

"It's strange that he was too excited when he raped a corpse for the first time." Nicha half-joked, then nodded and said, "But there is indeed such a possibility. Well... If this is the case, the murderer's residence or workplace should be at the intersection of the four crime scenes?"

Zhong Renlong added: "We have already investigated this direction."

What the two were talking about was the standard police investigation model, which is to draw a circle with the crime scene as the center. The intersection of the four large circles of the four cases is very likely to be the suspect's residence or workplace.

This model may sound superficial, but it has been verified many times. Because people are such simple animals in many cases, especially serial killers who act according to their instincts.

Nicha thought for a moment, looked at Jiang Yuan, and then asked Zhong Renlong: "Who was sent to investigate at that time?"

In the case of serial rape and murder, the Malaysian police has also invested a large number of police forces and investigated in multiple directions.

Zhong Renlong checked his phone and said, "The third group conducted a survey. They investigated companies within the area, retrieved information about owners and tenants of local apartment buildings, and also investigated accommodation in local hotels, etc."

"If that's all, then it's not enough. At least we have to go door to door and investigate." Jiang Yuan had just crawled out of the mud pit of Meiyang City. He knew as soon as he heard it that theirs did not meet the standard for investigation and could only be considered a visit at best.

But in this kind of case, if you send a dozen or twenty people to interview the people, hoping to find the person who is not of the people among the people, it would be too difficult and a bit of a luck-based approach.

Zhong Renlong smiled bitterly: "Without a search warrant, many people are unwilling to cooperate."

Jiang Yuan had experienced a similar situation in Malaysia before, so he nodded without surprise. After a moment of silence, he said, "From the current situation, the search is definitely not strong enough. However, we can take a look at other evidence first..."

The few of them finished the autopsy, went to the bathroom to wash themselves, changed their clothes, and went to the office upstairs together to read other materials.

The police had already compiled the footprints, fingerprints, preliminary investigation reports, etc. Jiang Yuan read through them one by one and also identified some of the main fingerprints.

Not much gain.

Although Jiang Yuan only spent a few hours on the investigation, the investigation was almost over at this point.

After marking a few fragmentary fingerprints and comparing them to no avail, Jiang Yuan decisively said, "Next, I suggest that we focus on the intersection points around the crime scene."

"The area around the dark zone? Although the designated area is not large, but... is it strictly enforced within the designated area? If it exceeds a few hundred meters, the scope of the investigation will increase a lot." Zhong Renlong raised a realistic question.

For relatively busy neighborhoods, if the investigation radius increases by 100 meters, the list of people to be investigated may increase by tens of thousands, which is a big challenge for the police force of any city.

So, what if the radius does not increase? Should we strictly follow the results of the paper drawing to define the range?

According to normal thinking, there is always some uncertainty in what anyone does. Even serial killers probably don't do things so accurately and uniformly. So how much should the radius be increased?

Jiang Yuan had followed Xu Taining in many battles, so he didn't say much at this time. He clearly followed the method he learned from Xu Taining and said, "Just strictly follow the designated scope and don't go beyond it. If we can't find it, we can expand it. But within the designated scope, we must conduct a thorough investigation. Can you do this?"

This is Xu Taining's idea. If you want to investigate, you must do it thoroughly. For example, the investigation done by Nicha and others before was not thorough, so now they have to consider the issue of secondary investigation.

Nicha and the others looked at each other, all a little hesitant, and discussed in a low voice, saying, "God Jiang, although we also want to check every household, it is indeed difficult to do so. Moreover, if our goal is to extract fingerprints and DNA, it will probably be even more difficult."

Jiang Yuan was stunned when he heard this. Since Xu Taining was here, he could only buy a return ticket.

Zhong Renlong also whispered: "God, our previous investigation has reached its limit. If we want to increase the scope and depth of the investigation, I'm afraid we need some evidence support, and perhaps a court summons and the help of a lawyer."

Zhong Renlong said this first in Chinese and then repeated it in Malay.

Miao Ruixiang listened and said: "Malaysia has made things more difficult. Rapists have to have more sex."

Zhong Renlong continued to translate, and Miao Ruixiang quickly said, "I just want to complain, no need to translate."

Jiang Yuan waved his hand when he heard this and said, "If the normal investigation has reached its limit, then let's leave it at that for now and think of other ways."

This is actually part of Xu Taining's investigation method. To investigate the matter thoroughly is essentially a comparative degree. It is hard to say how thorough it is.

Therefore, since Nicha and Zhong Renlong both believed that the local investigation had reached its limit, simply investigating this clue was also considered to be exhausted. For the police, this is not incomprehensible. There are many places in China that you cannot investigate as much as you want. In other words, before the popularization of DNA technology, no matter how thoroughly you investigate, it may not be thorough enough. Coordinates of the Baiyin case.

"In fact, the area that needs to be investigated is not particularly large. I would like to offer an idea. The footprints left by the suspect are very complete, and the gait can be judged by the footprints. If you can collect the gait data of the people within the investigation range, such as videos of them coming in and out, I can also make a direct judgment."

The solution proposed by Jiang Yuan is equivalent to being a humanoid gait analyzer - the cameras in domestic airports and high-speed rail stations are already able to independently analyze and match. Malaysia does not have such a system or a corresponding database, so Jiang Yuan just took the stage himself.

What Nicha and Zhong Renlong heard was very different. This was different from Jiang Yuan's previous performance on TV. This was a matter of two orders of magnitude.

At the TV station, Jiang Yuan might only need to look at a few dozen footprints and tracks, but if he were to watch a video and analyze the footprints and gaits in an area, there would be more than tens of thousands of people.

"Is it really possible? Will it be too hard?" Nicha put away his shock and replaced it with admiration and a hint of embarrassment.

"The clues are stuck here. It's not that hard or not. I can watch three to five hundred sets of gaits in an hour, and only one to two hundred footprints. You should try to collect as complete videos as possible." Jiang Yuan was not talking casually. Solving cases by simply watching videos has long been known in China. In some cases, thousands of police officers are organized to watch videos.

However, observing gait is much easier than other methods, it just requires higher technical skills.

Jiang Yuan said this, looked at the time, and said, "That's it for today. I'm going to bed early. Thank you for your hard work. I will officially start watching the video tomorrow afternoon."

This period of time is used for Nicha and others to collect, analyze and even edit videos.

Nicha and others fully understood and hurriedly expressed their gratitude, and respectfully sent Jiang Yuan and others to the car.

According to Huang Qiangmin's request, the hotel booked by the Malaysian police was also quite good. Jiang Yuan stayed in a suite, took another shower and went to bed.

Because Miao Ruixiang was Jiang Yuan's junior, he got a separate king-size bed room not far from the others. Miao Ruixiang also took a shower first, changed his clothes, and then took out a statue wrapped in red cloth from his suitcase.

Miao Ruixiang placed the red cloth statue respectfully on the table, lit three incense sticks, and then uncovered the red cloth. A wooden statue of Jigong Bodhisattva appeared in the midst of green smoke.

Miao Ruixiang bowed, took out his mobile phone in front of him and made a video call to his master Wu Jun.

　I socialized a lot today and drank half a catty of wine, meow~
　　
　
(End of this chapter)