National Forensic Doctor

Everyone had something to do, except Wang Bo, who neither had a job nor was assigned to work, so he silently took out his mobile phone, took a few photos, and sent them to the work group.

Technicians working in the work group such as trace inspection and field survey have already been dying of curiosity.

At this time, I saw the news that fingerprints were newly discovered, but I instantly entered the shock mode.

The presence of fingerprints means that it is possible to directly identify the murderer. It is surprising that such important evidence was not found or found.

Li Yuanliang: "Did Jiang Yuan find the fingerprint? Where is it that we can't scan? @Wang Bo"

Wang Bo then sent another photo showing the location of his fingerprints. That's the bottom of the window frame, which should be a relatively obvious location. Li Yuanliang: "You didn't catch this? Are you kidding me?"

Wang Bo: "It was a fingerprint that was pressed quickly. It was not obvious. Jiang Yuan used toner from a laser printer, mixed with magnetic powder, and brushed it several times before it came out. When I first saw it, I thought it was very magical. , it’s not the same as ordinary powder coating.”

Wang Shouming: "Can you still make flowers by painting with powder?"

Wang Bo: "On the first pass, there was still nothing, and then the second pass showed a little bit of fingerprint marks, which had to be illuminated with a survey light. After two or three more repeated passes, it gradually became obvious." This is the first time I’ve seen such powder coating.”

Normal fingerprint brushing is to sprinkle powder on it and the fingerprint will be revealed. Sometimes it is not clear. In fact, it means that there is not enough sticky powder on it. Then add a little more powder and it will be almost there.

Fingerprints made with printer toner mixed with magnetic powder have to be swiped three, four, or five times, and the pattern gradually becomes clearer. This is something Wang Bo has neither seen nor learned.

The work group in Changyang City became quiet.

After a while, someone spoke again: Li Yuanliang: "I asked an expert and they said that laser printer toner has a lightness close to copper powder and aluminum powder, and the specific gravity is between aluminum powder, copper powder and magnetic powder. and has slightly weaker magnetism than magnetic powder, mainly due to its own electrostatic properties. In addition to being used alone, it can also be mixed with magnetic powder in different proportions according to seasonal and environmental changes, which can promptly make up for the long-term brushing of magnetic powder. The phenomenon of small particles being lost in the display... What the hell, do you need to refresh the display according to the season and environment?" Wang Shouming: "It's fake. If it's so useful, just put it in our survey box. Isn't that a big deal?" Li Yuanliang : "I'm going to repeat what the expert said. I didn't say it. Please explain in advance. The person's original words are: If you are not an expert, using printer toner will only be self-defeating. For those who can use toner skillfully, kneel down and shout long live. That's it.

Wang Shouming: "How can any expert speak like this?

Li Yuanliang: "My uncle said it."

Wang Shouming: "...Uncle is really right, long live long live long live!"

Wang Bo's forehead felt swollen from looking at it.

Although the people chatting in the work group were all colleagues and there were leaders in it, Wang Bo couldn't help but think carefully about his words.

Wang Bo: "When I was in school, the professor taught me not to brush the display multiple times. He said that if you are satisfied with the display once or twice, it is fine. If you are not satisfied, brushing the display multiple times will easily drag the lines that have already appeared. Destroy, or appear pitch black, only in extremely dry environments are multiple brush strokes allowed..."

Wang Shouming: "Xiaobo, although I don't understand it either, let me tell you that for things like theory, just listen to it. To see the big guys doing things, calling 666 is the safest way."

Li Yuanliang: "Don't teach young people bad things. This issue can be discussed. I just checked some information...

The method used by Jiang Yuan has a very complicated proportional configuration. Don't think about it. I think the key to the problem is, why did he refresh the window sill multiple times? What did he find? @王波";

Wang Bo: "I found the footprints."

Wang Bo then described the situation after Jiang Yuan's arrival. Both technicians and non-technicians in the work group fell silent. The footprints found by Jiang Yuan did not need to be displayed; it should be said that they were there, but everyone saw too many footprints, and no one thought of looking down from the window.

The second floor of the color steel house is similar to the normal second floor, with a height of about 3 meters. Normal surveyors will go to the second floor to

If you go to the room on the upper floor to investigate, you won't think that the murderer's route is to jump out of the window.

Why bother? So far, no witnesses have been reported. The door was open. The murderer just walked in and smashed the cashier to death. Why didn't he just walk through the door? Li Yuanliang: "An accident must have happened. Otherwise, if the murderer walked through the door normally, he would leave neither fingerprints nor footprints, at least it would be indistinguishable."

Gao Long: "It was an accident to beat the cashier to death. Normally, I wouldn't think of beating someone to death."

Li Yuanliang: "Are you too excited?"

Wang Shouming: "It's normal to be emotional. Anyone who participates in robbery must have accelerated adrenal gland secretion. It would be too scary to get used to it. There should be no such Liangshan people now."

"Xiao Bo." He Guohua shouted, waking up Wang Bo who was immersed in his mobile phone.

"Hey, let me see what the group says." Wang Bo quickly smiled at his master.

He Guohua said seriously: "Take Brother Jiang to the survey vehicle and turn on the computer."

"Okay. Are you using the backend?" Wang Bo asked quickly.

Jiang Yuan himself said: "I want to compare fingerprints on the computer."

He just marked the feature points on his mobile phone once, but failed to match. After refreshing the display again, he took pictures again and was ready to use the computer to compare. After all, the size of the screen is still very important. When looking at fingerprints on a mobile phone, many details cannot be seen clearly.

Wang Bo responded quickly and took Jiang Yuan down from the color steel room.

The two of them walked slowly along the acrylic bridge. Wang Bo walked a while and couldn't help but whispered: "Brother Jiang, um, why did the murderer jump from the second floor?"

Jiang Yuan heard strong curiosity from Wang Bo's tone. Jiang Yuan glanced at Wang Bo and thought about it: "Can we wait until we find the murderer before questioning him?"

"This...can't I just ask?" Wang Bo felt itchy all over and was a little disappointed. Can the case you asked about be called a detection? Jiang Yuan could detect the awkwardness in Wang Bo's body, smiled, and asked, "Do you have to guess?"

Wang Bo was really excited: "What do you think the reason is?"

"I'm too lazy to guess. I'm not interested." Jiang Yuan said bluntly, "I just want to do technology. For me, finding footprints is more interesting than fingerprints or DNA."

Wang Bo said "Ah": "No, even if we are in the technical field, this is it, but this is it..."

He said it twice, most likely using polite language: That's it?

Jiang Yuandao: "Liu Jinghui and Liu Chu from the provincial department are probably more in line with your requirements. He likes to play reasoning."

"He is the kind of pure guesser... No, the kind of pure reasoning, I don't like him either." After Wang Bo finished speaking, he felt a little embarrassed and said hurriedly: "I'm not talking about work, nor am I saying that his methods are not good. Well, it’s just different personal interests and hobbies.”

Jiang Yuan expressed his understanding that people are diverse. The more you work on cases and watch them, the more you can understand this. Some people like power, some people like money, some people like women, some people like Japanese dogs, and some people like to play reasoning, or like Wang Bo, they like technology and reasoning...

Jiang Yuan made a big breakthrough in the case. Wang Bo felt different when he looked at Jiang Yuan again.

While talking now, Wang Bo also gradually relaxed and couldn't help but said: "If we simply use technology to solve crimes, I think there are limitations."

Jiang Yuandao: "That's for sure."

Wang Bo: "What I mean is that if you hadn't judged the murderer's movement, or if he jumped and landed on a clean cement floor instead of land, without leaving any footprints, or if he had If we clean it up directly, will our case not be able to continue? Thinking about it this way, it feels very difficult."

Jiang Yuan shook his head: "It will get harder, but it won't make it impossible."

"Is there any other way to do it?"

"Of course. The most direct solution is to scan the entire room. Take out all the footprints, and then compare them with the movement of the footprints outside."

“This is a lot of work

Bar. "

Jiang Yuan glanced at Wang Bo and said: "So many people are idle, what's the workload to worry about? To do murder cases, as long as there is a plan, manpower expenditure is the responsibility of the detachment leader."

"Ah...this..." Wang Bo had to admit that this plan really might bring out the murderer.

Despite the large number of footprints on the construction site, only a few people would enter the cashier's office, probably only about 10 people. Then find the footprints of these people, draw a map on paper, and draw the movement lines. There will definitely be a few footprints with a low degree of suspicion, and a few footprints with a high degree of suspicion. In this case, the scope of the murderer can be narrowed to a certain extent.

Jiang Yuan continued: "In this case, if you check the footprints backwards, you may find that there is a set of footprints starting from below the teller's window. In this case, there is still a certain probability that the fingerprints at the window will be discovered."

Wang Bo nodded subconsciously. Indeed, if you use this method, as long as you are careful enough, you will definitely be suspicious if you find footprints under the teller's window.

"If the footprints in the room are carefully sorted out, it is possible to discover the murderer's movement. On the contrary, it will take a lot of effort to discover the murderer's fingerprints." Jiang Yuan himself was also summarizing. Wang Bo deeply agrees: "Probably many people don't know how to mix magnetic powder with toner."

"Looking at the bright side, if the murderer had been wearing gloves, he wouldn't have been able to leave any fingerprints."

"Yeah, what should I do?"

"So it's always good to master a little more technology." Jiang Yuan paused, thinking about it himself, and said: "If the footprints can be determined, we can find the means of transportation when the murderer came here, and there may be a breakthrough."

Wang Bo was stunned: "That's right. I couldn't find transportation before because I didn't have a handhold. Now that I have footprints, I can find transportation. Should I report this to the leader?"

"You can call and report." If there are new clues, it is natural to investigate them.

Of course, Jiang Yuan is more concerned about fingerprints now.

However, as he said just now, there are so many people. It is not a bad thing to follow the transportation and get more clues and evidence. When the survey vehicle arrived at the entrance of the construction site, Jiang Yuan got the computer, connected to the intranet, and checked the fingerprints himself.

At about the same time, more detectives and technicians also started moving.

Yu Wenshu is indeed very interested in new clues and investigation directions. Fingerprints are not guaranteed to yield results, and he is definitely willing to expand the direction of the investigation.

The walkie-talkie left in the survey car also rang twice from time to time. Everything inside and outside the construction site was now in operation.

Inside are technicians who are fixing the footprints, and outside are criminal police officers running around looking for transportation.

Not far from the construction site, there are increasingly prosperous markets and shops. The places that are not covered by the police surveillance videos and are being avoided may be covered by someone else's video. However, this requires a family. Home inquiry checked.

Jiang Yuan pulled out the fingerprints, carefully made characteristic points, and then compared them carefully...

"Well, it's because the screen is too small." It didn't take long for Jiang Yuan to match his fingerprint.

Not surprisingly, the suspect Qi Penghu is a fugitive who has been sentenced for theft and robbery and was also involved in the gang organization case. Qi Penghu in the photo has short hair, a short nose, a big mouth, rough skin, and swollen eyes. Knife marks...

With a fierce appearance, he looks like it would be hard to find a normal job.

Jiang Yuan made a submission in the background of the system, stretched and looked around.

The construction site is called "Binhu Spring Greening Landscape Project". It is located in the old city of Changyang City. There are many bustling areas nearby. People passing by shopping or local residents walking around will be curious to see what is going in and out here. The police and police cars, as well as some brave but bored ones, just stood nearby and watched.

Jiang Yuan turned around and saw a man with a special appearance, about thirty years old, with short hair, a short nose, a big mouth, rough skin, and knife marks at the corners of his eyes...

Jiang Yuan lowered his head again and silently glanced at the photos on his notebook, feeling a little regretful that he had come this time.

I was so anxious that I didn't even call Mu Zhiyang over.