Police officer Chen Shu

Chapter 767 The Criminal Returns to the Scene

Back at the Criminal Investigation Department, Chen Shu went to Huang Mao's office and asked Zhu Yiba and Huang Mao if they had noticed anything unusual in the video surveillance footage.

Video investigation is a technical skill, and it is handled by specialized technical personnel in the criminal investigation brigade. In some areas where cases occur frequently, a special video investigation team may even be established.

There are two main tasks: first, to respond to police calls at the scene, and second, to search for civilian video footage near the crime scene, copying any video surveillance footage that captured the scene.

The second method involves sitting in the office, pouring yourself a pot of tea or making a couple of coffees, and then spending a long time analyzing the situation. If you really want to compare it, it's a bit like an advanced version of a "spot the difference" game, extremely taxing on both your brain cells and eyes.

Ordinary people think that video investigation is just checking surveillance footage, and that it's a very simple thing, just staring at the screen to find criminal suspects.

Actually, that's not the case; there's a lot to learn about it.

Police universities and criminal investigation colleges offer specialized video investigation programs for local video investigation personnel to study and further their education. These programs are often held in several sessions, because a single week of intensive training is simply not enough to explain the material clearly.

Furthermore, with the development of science and technology, the information technology it encompasses has increased exponentially. After all, it is a new technology, and this field is still a blue ocean.

Besides the necessary knowledge, checking surveillance footage and retrieving call records both require sufficient patience and a very long time; neither can be neglected.

After receiving confirmation that everything was temporarily normal, Chen Shu copied the video to another computer and began video investigation simultaneously, but he only selected the camera in the corridor where the crime scene was located.

Then, I started watching it frame by frame.

Chen Shu stared at the screen for a moment, not daring to blink, but his mind was racing, trying to figure out the connection between the curtains and the muddy grass.

Curtain fabric, muddy grass;

Upstairs and downstairs.

The three spent the entire afternoon in the office without finding any clues. After returning from the scene re-examination, Ma Rongcheng brought back a bunch of fingerprints, intending to put them all into the fingerprint database later.

When the fingerprints are compared with the hotel's guest information, if any extra people appear, they are likely criminal suspects.

In the eyes of Ma Rongcheng, a professional and technical police officer who came down from the provincial department to provide support, this was a rather clumsy method that did not reflect his status as an expert.

Ma Wing-shing patted Chan Shu on the shoulder, signaling him to move to a different spot.

After sitting down, Ma Rongcheng typed in a URL, uploaded the copied hotel video to the website, and then pressed enter to finish.

Watching the steadily rising progress bar and percentage on the screen, Ma Rongcheng smiled easily, displaying the demeanor of a master, and then led the group downstairs to have dinner.

Inside the restaurant, Ma Wing-shing held up his chopsticks, introducing the restaurant with a hint of pride.

"The WoAn Intelligent Video Investigation System is supported by modern technologies such as big data, cloud computing, and the Internet of Things, uses artificial intelligence analysis as a means, and integrates various digital services within the public security intranet to comprehensively perceive and analyze data."

"Teacher Ma, is this the Sky Eye system that our Ministry of Public Security recently launched?" Jiang Hai maintained the learning attitude that a student should have.

Ma Rongcheng replied with a smile, "They're different. The Sky Eye system integrates our own public security surveillance equipment, while the WoAn system is mainly used to analyze civilian surveillance videos."

The question-and-answer session between the two left Chen Shu and the others listening in awe. With the development of science and technology in today's society, various investigative techniques are emerging one after another, and these are things that can really be of help.

Unlike in the past, when police officers, apart from wearing uniforms and being different from ordinary people, were basically forced to investigate cases in a rudimentary way, using the most primitive methods, such as investigation and visits.

The expenditure of police resources, material resources, and financial resources is completely disproportionate to the severity of the cases.

After the group finished their meal and returned to the office, the system's analysis results were already available on the computer.

Jiang Hai respectfully pulled out a chair, allowing Ma Rongcheng to sit in front of the computer all to himself, while the others stood in a semi-circle behind the expert, looking at the analysis report on the computer together.

The text filled half the screen, but upon closer inspection, there was nothing there.

According to the system's conclusions, the intelligent system, which reportedly cost astronomical sums to develop, did not find any suspicious persons in the videos taken within twenty days of the incident.

Everyone was inevitably a little discouraged.

Considering the possibility that the suspect might return to the scene, Chen Shu suggested that the video surveillance footage from the week following the incident be copied into the software for analysis.

The term "returning to the scene" refers to the high probability that a criminal will return to the crime scene after a period of time following the crime.

There are quite a few real-world examples to support this.

The first type of criminal may have a high tendency to seek thrills; their purpose in committing crimes is to seek adventure, excitement, and inner satisfaction. After leaving the crime scene, they may return to it. This behavior provides them with a more intense sensory stimulation than when they committed the crime.

The second category involves criminals returning to the scene to confirm the consequences of their previous crimes. This could include whether any evidence identifying them was left behind, whether they destroyed evidence accidentally left behind during their previous crimes, or to observe the progress of the police investigation.

From a psychological perspective, it's to evade police action.

These are roughly the two categories mentioned above. The first category is extremely rare, and the vast majority belong to the second category.

Jiang Hai, who also belonged to the police academy faction, seemed to understand but not quite. He habitually moved closer to Chen Chuan and whispered, "Brother Chuan, why do these people return to a scene full of police officers after committing a crime? Isn't that just courting death?"

Chen Chuan crossed his arms, glanced sideways at his junior brother, and said disdainfully, "Little brat, think back, do you ever look back after you've finished pooping?"

Rough words are not rough.

Jiang Hai was shocked and actually recalled it for a while.

After a moment of realization, he was still a little confused. This young police academy student didn't know whether it was right or wrong for him to ask this unreliable senior a question.

Here, Ma Rongcheng, as an expert, immediately agreed with Chen Shu's suggestion and then asked Huang Mao to go to the hotel to retrieve the videos from recent times. After Huang Mao returned from the hotel, he put the videos into the software and analyzed them again.

The computer fan was blowing hard like an ox panting, but the analysis still showed no suspicious persons.

Ma Rongcheng was somewhat embarrassed. He had just spent half a day supporting the Woan system, but after a series of vigorous operations, he hadn't produced anything useful. This made the expert from the provincial department feel a little embarrassed, and he felt as if the chair under his buttocks was burning hot.

"How about we let Old Tang dissect the body?" Ma Rongcheng suggested, choosing to avoid the question.

Jiang Hai immediately took out his phone, somewhat expectant, but knowing he couldn't make the decision himself, he asked in a questioning tone, "Will I contact Teacher Tang as soon as I arrive?"

As he spoke, he suddenly seemed deflated, muttering, "I doubt the family will agree to an autopsy."

Looking at the young man with such a rich expression, Ma Rongcheng chuckled and said, "For autopsies of unnatural deaths, we only need to notify the deceased's family; we don't need to get their consent."

"Is that so?" Jiang Hai jumped up, picked up his phone as if to dial a number, but his eyes were fixed on his senior brother beside him.

Chen Shu didn't express his opinion, but stared at the analysis report on the computer monitor, rubbing his chin as he pondered.

It must be said that this Woan intelligent video system is quite capable. Although its analysis conclusions are somewhat rigid and mechanical, it has clearly compiled some tedious data.

Once the table is pulled up, the time, place, and people involved are clearly listed.

After connecting to the personnel data of the public security intranet, it can display the personnel information of anyone whose face is clearly visible in the surveillance, even those wearing masks.

Then, the total duration of each person's appearance in the surveillance footage was marked next to their name.

Clicking on a person's name will bring up a list of the times that person appeared in the videos and the corresponding video clips.

The first few people on the list were naturally hotel staff, and the rest were locals from Kunming who frequently visited the hotel. According to normal investigative logic, these people should be investigated one by one.

But Chen Shu and his team were police officers from another province, so it wasn't easy for them to start this kind of investigation on their own.

Chen Shu stared at the names on the screen, and subconsciously looked at the person ranked first, which meant the person who had been in the video the longest.

Zheng Amei.

Zheng Amei, a hotel cleaner, is responsible for cleaning rooms on each floor that have been checked out. Naturally, she spends the most time and covers the widest areas among all the staff.

This person was also the first to discover the crime scene.

That day, since Chen Shu, Chen Chuan, Jiang Hai and others were all present, after Zheng Amei opened the door and screamed upon discovering the body, the three of them quickly entered the room and found the deceased.

Therefore, Chen Shu and others naturally assumed, and subconsciously assumed, that they were also the first to discover the body, thus ignoring Zheng Amei, who was the first to discover the body.

This hotel staff member had an extremely low profile.

The problem lies here.

Chen Shu raised an eyebrow. The case seemed to be making progress, but he also knew that the real challenge was just beginning.

(End of this chapter)