Criminal Investigation Notes

Su Hui stood up, and he leisurely introduced: "This is just a simple schematic diagram, time is limited, I didn't draw it in a standard way, just to introduce the principle to everyone. The method I used today is not what everyone understands. It is a branch of the criminal psychological profile, which is called GeographicProfiling, which is also a criminal geographic profile. Its principle is to combine the perpetrator and the victim with data such as the encounter location, attack location, killing location, and body throwing location. the criminal minds of the criminals, and deduce the criminal's residence, the location of the dismemberment, the place of work or the possible foothold."

Su Hui continued: "Actually, this theory just sounds advanced, and there were some sayings among many old detectives in the past. Also, 'not close, not far, not repeating'. In fact, these are the basic principles of criminal geographic profiling, but what I deduce now is more systematic."

Then Su turned around to face the crowd and explained in detail: "If there is no crime location, there will be no crime. The choice of location by criminals is not random, we need to look for the rules, and there are some basic theories, which everyone may also understand. For example, the circle hypothesis theory, that is, the circle of crime: the distance of a straight line connecting the two most geographically distant cases in a series of homicide cases is the diameter, and the focus of the line is the center of the circle, forming a circle at a time.”

Su Hui's voice was a little low, and he talked eloquently, looking like a teacher who was teaching students, but now, all the criminal policemen who had worked in the serious crime team for several years were in front of him.

“…and the theory of environmental criminology, and the principle of foraging are some of the theories that underlie geographic profiling of crime. Crime only happens when the perpetrator and the potential victim are in the same place at the same time, and now we’re in In the era of big data, geographic information used by police should be combined with crime maps and applied in practice.”

In the conference room, everyone was attentively listening to Su Hui's explanation for a while, silently.

Although some of them have heard of these theories, they do not have such a deep understanding, and they have no experience in applying them to practice.

"Although the actual clues we have now won't allow us to find the murderer right away, we have already given us a lot of information..."

As he spoke, Su Hui tapped the three red dots on the picture with a pen, "These three places are the places where the murderer stored the stumps and handed them over to the client. According to the testimony, we can know that these places are the murderers. Selected."

Then he clicked the three yellow dots next to him: "These three places are the original work places of the waiters before they disappeared. We have already learned about these places, which means that the murderer has been to these places at some point in time. ."

Su Hui's mouse point, using these points as the center, draws several intersecting circles.

"Several geographic portrait modes commonly used in the world are: Rosmo mode, Kanter mode, and Caining mode. I use the police's GIS here. Based on this location information, we can optimize it according to the urban terrain, and we can deduce it. The following picture is to help us find the source of evil..."

Having said that, Su Hui closed the previous schematic diagram and opened a professional software.

A rainbow-colored map of Huadu appeared on the projection.

Su Hui circled the red part of the picture with the mouse and concluded: "It can be known from the calculation that the suspect's fixed attribution point is likely to be within this area."

Su Hui's explanation is not complicated, and he omits many parts that need to be calculated. It sounds easy to understand and has sufficient theoretical basis.

Qu Ming heard this, looked at the map on the screen, and coughed lightly.

Xia Mingxi had only been to some relevant theories before, but had not practiced them in practice. She felt that Su Hui explained it very well, and she had to pick up problems with her conscience: "Yes, but this area is still very large..."

"Yes." Su Hui nodded in agreement.

Xia Mingxi didn't expect that Teacher Su would recognize him so happily, and pursed his lips, wanting to hear what he would say next.

"With the current serious crime team and the police force of the General Administration, even such a large area needs to be investigated for a long time. Therefore, I based on the murderer's transportation, class, age, education, and the necessary conditions for committing the crime, the geographical location is adjusted. rigorous screening."

Qu Ming asked: "What are your screening conditions and criteria?"

"It's the unique behavior pattern of the murderer." Su Hui said, leaning his body on the table, and holding the cat's head on the scepter with the other hand, "For example, why is his victim a coffee shop clerk? ?"

Xia Mingxi thought for a while: "The murderer is a person who likes elegance and likes to drink coffee?!"

Su Hui said: "It is very possible to like elegance, but it is wrong to like coffee. The murderer's multiple purchase receipts did not show coffee, and he did not drink coffee in the coffee shop. This is also one of the characteristics of the murderer. I think that coffee shop It has a certain meaning for the murderer. Also, our screening conditions are related to his age, education, and property status. This is not discrimination, but science. Most of the bottom workers will not come and go from time to time. A lot of cafes, and they stay there for a long time. Their time and financial situation do not allow it.”

Zheng Bo followed his train of thought and thought deeply: "In other words, the murderer chose the coffee shop for a reason..."

With Su Hui's mouse click, the colors of some areas near farmers' markets, construction sites and other areas have dimmed, and the number of areas to be investigated has been reduced by most.

"According to several surveillance reports, the time of the murderer's visit to the coffee shop is not fixed. Most of the time is in the afternoon. What kind of work might he be doing?" Su Hui continued.

"It should be a job with relatively free time...or a job with changing shifts..." Qiao Ze answered.

Su Hui coughed twice and continued: "Those low-level employees who live in groups, or busy white-collar workers, have relatively little personal space and time, and it is difficult to make others unaware. According to these conditions, we can carry out Screening to exclude some areas."

The area on the map is further reduced.

"Then the next question, his transportation should be a private car, how did he choose those cafes? Where did he change the women's clothes? When did he commit the kidnapping? Where did he then take the victim? Also, after the hands and feet were cut off, what did he do with the rest of the body? Where was it stored?"

Everyone couldn't help but follow Su Hui's voice and ponder these questions.

"I read the time of the women's disappearance, and also read the forensic report. The murderer did not cut off their hands on the day of the murder, where he may have kept them for a period of time, and he must have to go back and forth many times. The place where the body is imprisoned and dismembered must be large enough, quiet enough, and safe enough not to be noticed.”

Su Hui continued: "At the time of inference, the murderer's corpse operation room is fixed, and once the coffee shop is selected, it is fixed, which gives us more hypothetical routes. And when the murderer performs dangerous behavior, Will take the initiative to avoid downtown."

Having said that, Su Hui's mouse was another point, and several simulated paths represented by dotted lines appeared on the map.

Then, several small circles of different colors appeared on the map.

Su Hui raised his head and concluded: "Now, I can confirm that the murderer's corpse may be located in these red areas, and his residence is likely to be in the blue area. If his residence is also The place where the corpse is divided will be in the purple area, and the darker the color, the greater the possibility."

If the first picture Su Hui showed was rough and rudimentary, the later pictures became more and more professional, and now this picture can be described as high-end.

This teacher Su really used ten minutes to circle the possible hiding places of criminals with a method that they can understand...

The whole process is like magic.

Lu Junchi stood with his arms folded, watching as Su Hui's explanation deepened, the expressions on the players' faces changed from initial doubts to admiration and surprise. He said to several subordinates: "You can start with the dismemberment site, focus on the purple area, and also inspect the blue and red areas."

The crowd kept nodding.

Su recalled something and reminded: "By the way, what I did is just a data model, which can only be used as a reference for the judgment, and it is based on the fact that there is only one murderer and so on. You still have to be careful and serious, and use actual evidence. operation, and some special cases cannot be ruled out..."

Lu Jun nodded slowly: "We will combine the actual situation."

Su Hui held the scepter, hesitated for a moment, and then said: "Because the time is a little tight now, I will make another bold prediction..."

Seeing that he hesitated, Lu Jun nodded and said, "Teacher Su, don't worry, we will only use it as a reference."

After several contacts, he knew that this teacher Su was very taboo against unsubstantiated psychological profiles, and he was afraid that they would take this as a criterion and ignore other clues.

Su Hui then continued: "There are 232 cafes in the entire range of the murderer's activities. Some of these cafes are too big or too small, and some are too biased. These are not in line with the murderer's choice. Rules. After screening, a total of 34 basically match, and he has committed crimes in three of them, which means that the murderer will give up and continue to commit crimes in some coffee shops nearby these three. "

The cafes on the map were darkened one by one, and finally there were only five light spots left, which were still flashing.

Su Hui pointed to the results on the picture below and said, "The murderer's next murder location is likely to be within a week, in these five cafes."