Criminal Investigation Notes

Su Hui stood up, and he introduced leisurely: "This is just a simple schematic diagram, time is limited, I didn't draw it very standard, I just used it to introduce the principle to you. The method I used today is not understood by everyone The criminal psychological portrait, but a branch of it, is called Geographic Profiling, which is also a criminal geographical portrait. Its principle is to combine the perpetrator and the victim's encounter location, attack location, killing location, and dumping location, etc. The criminal mind of the criminal can be drawn to the residence of the criminal, the location of the body, the place of work or the possible destination of the criminal."

Su Hui continued: "Actually, this theory just sounds profound. There were some sayings among many old criminal policemen before, such as 'throwing far away and burying close' when throwing corpses, 'head far away, body close', 'small near, big far', Also, 'not near, not far, not repeated'. In fact, they are all the basic principles of criminal geographic profiling, but what I have deduced now is more systematic."

Then Su Hui turned to face the crowd and explained in detail: "There is no crime without the location of the crime. The criminal's choice of location is not haphazard. We need to find the rules. There are some basic theories in it, and everyone may understand it." For example, the theory of the circle hypothesis, which is the circle of crime: the distance between the two cases with the farthest geographic location in a series of homicide cases is the diameter, the point of the line is the center of the circle, and a circle is formed at one time."

Su Hui's voice was a little low, and he talked eloquently. He looked like a teacher who was teaching students. However, the people in front of him were all criminal policemen who had been working in the serious crime team for several years.

"...and environmental criminology, and the foraging principle. These are some of the theories underlying the geographic profiling of crime. Crime only occurs when the offender and potential victim are in the same place at the same time, and now we're in the In the era of big data, the geographical information used by the police should be combined with the crime map and applied in practice."

In the meeting room, everyone was listening to Su Hui's explanation with rapt attention, and there was no sound.

Although they have heard of some of these theories, they don't have such a deep understanding, let alone the experience of applying them in practice.

"Although the actual clues we have obtained in this case cannot allow us to find the murderer immediately, it has already told us a lot of information..."

While talking, Su Hui clicked on the three red dots on the map with a pen, "These three places are where the murderer stored the stumps and handed them over to the client. According to the testimony, we can know that these places are all places where the murderer Selected."

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

Su Hui clicked the mouse and drew several intersecting circles with these points as the center.

"Now the commonly used geographic portrait models in the world are: Rosmer model, Kanter model, and Cai Ning model. I used the police GIS here. Based on these location information, we can optimize it according to the urban terrain, and then we can derive Draw the picture below to help us find the source of the 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: "Through calculations, we can know that the suspect's fixed attribution point is probably within this area."

Su Hui's explanation is not complicated, and many parts that need to be calculated are omitted. 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 learned some related theories before, but had no practical experience. She felt that Su Hui's explanations were very good, and she still had to pick faults against her conscience: "Yes, but this area is still very large..."

"Yes." Su nodded in agreement.

Xia Mingxi didn't expect that Teacher Su would admit it so quickly, so he pursed his lips, wanting to hear what he would say next.

"With the current serious crime team and the police force of the General Bureau, it takes a long time to investigate even such a large area. Therefore, according to the murderer's means of transportation, class, age, education, and the necessary conditions for committing the crime, I divided the geographical location and Sophisticated screening was carried out."

Qu Mingfa asked, "What are your screening conditions and criteria?"

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

Xia Mingxi thought for a while: "The murderer is someone who loves elegance and coffee?!"

Su replied: "It's possible to like elegance, but it's wrong to like to drink coffee. The murderer didn't show coffee in the multiple purchase receipts, and he didn't drink coffee in the coffee shop. This is also one of the characteristics of the murderer. In my opinion, the coffee shop It has a certain meaning to the murderer. Also, our screening conditions are related to his age, education, and property status. This is not discrimination, but science. Most bottom-level workers do not often go in and out of There are many coffee shops, and they stay for a long time. Their time and economic situation do not allow it.”

Zheng Bai followed his train of thought and thought deeply: "That is to say, there is a reason why the murderer chose the coffee shop..."

As Su Hui clicked the mouse, the colors of some areas near the farmer's market and construction sites became darker, and the area to be investigated decreased by half.

"According to several surveillance reports, the murderer's visit to the coffee shop is not fixed, mostly 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 shift changes..." 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. Based on these conditions, we can conduct Screening, excluding some areas."

The area on the map is further reduced.

"Then the next question is, his means of transportation should be a private car. How did he choose those coffee shops? Where did he change the women's clothes? When did he commit the kidnapping? Where did he take the victim? Also, after cutting off the hands and feet, how did he deal with the rest of the body? Where are they stored?"

Everyone couldn't help following Su Hui's voice, thinking about these issues.

"I read the disappearance time of those women and the forensic report. The murderer did not cut off their hands on the day of the murder. He may have kept them for a period of time. He must have traveled many times. The place of imprisonment and dismemberment must be large enough, quiet enough, and safe enough that no one will notice."

Su Hui continued: "When inferring, the murderer's dissection operating room is fixed, and the coffee shop is also fixed once the coffee shop is selected. This gives us more hypothetical routes. And when the murderer performs dangerous behavior, Will take the initiative to avoid the downtown area.”

Speaking of which, Su Hui's mouse clicked again, 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 place where the murderer's body was dismembered may be in these red areas, and his residence is likely to be in the blue area. If his residence is also in the The place where the body is dismembered 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 simple, the later pictures became more and more professional, and now this one can be described as high-end.

This Teacher Su really spent 10 minutes, using a method that they could all understand, to circle out the possible hiding places of the criminals...

The whole process is like magic.

Lu Junchi stood aside with arms folded, watching as Su Hui's explanation deepened, the expressions on the faces of the team members changed from initial doubts to admiration and surprise.He said to several subordinates: "You can start with the dissection place first, and focus on the purple area, and the blue and red areas should also be inspected."

Everyone kept nodding.

Su recalled something and reminded: "By the way, what I did was just a data model, which can only be used as a reference for judging the case, and it is based on the fact that there is only one murderer, etc. You still have to be cautious and serious, and use actual evidence to judge To operate, let alone rule out some special cases..."

Lu Junchi nodded: "We will combine the actual situation."

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

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

After several contacts, he knew that Teacher Su was very taboo about psychological profiling without evidence, and he was also afraid that they would use it as a criterion and ignore other clues.

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

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

Su Hui pointed to the result on the picture below and said, "The murderer's next attack location is likely to be within a week, in one of these five coffee shops."