"Where is Li Goudan's family, does he live alone?" asked Li Tie.

Lu Zhiyong sighed and said: "Alas, Li Goudan and his parents are both working in other places, and now it is time for the wheat harvest, and Li Goudan has a field at home, so he comes back to harvest wheat alone." I didn't expect such a thing to happen, it's really miserable, the young man is only in his twenties, and he hasn't married a daughter-in-law yet. ”

Lu Zhiyong pointed out the way to Shao Dong as he spoke, and it didn't take long for him to come to Li Goudan's residence.

The door of the tiled house was surrounded by nearby villagers, and a few strong men arranged by Lu Zhiyong guarded in front of the door to prevent people from entering, so as to prevent the evidence of destroying the scene. When the villagers saw the police car coming, they all whispered, Lu Zhiyong jumped out of the car and shouted: "Come, come, let go, the county police officers are here, and the villagers are all conscious and give way." ”

Li You's apartment has four bungalows and a small courtyard, which has a fruit tree, and the courtyard is surrounded by walls that are more than two meters high, and the main entrance of the small courtyard is an old-fashioned wooden door with an iron deadbolt.

The wooden door flashed, and as soon as Li Tie pushed the door, the bolt was not inserted, and it opened with a "squeak".

"This is Li Goudan's home. Go in and take a look, I don't dare to look at it, I'm too scared. Lu Zhiyong said.

Li Tie and the others walked in with the toolbox for the scene investigation, although everyone in the first squadron of the criminal police was used to seeing the murder scene, they couldn't help frowning.

The scene was really miserable, there was a strong smell of blood everywhere, the deceased was wearing a sweatshirt and pants, barefoot, face down on the east side of the courtyard, a large pool of blood under his body, there were several obvious knife wounds on his neck, and the blood stains under his body had dried up.

The foundation of Li You's house is relatively high, so two short rows of stairs with only six steps were built from the house to the courtyard.

From the location of the deceased to the east staircase to the interior of the residence, there is a trail of bloody footprints.

Shao Dong followed the footprints until he walked to the bedroom in the residence, entered the living room, and immediately smelled a strong smell of blood, the ground was covered with bloody footprints, and he came to the bedroom along the blood stains, only about ten square meters of bedroom, a bed occupied a small half, and there was a very thin quilt on the bed.

The whole bedroom was covered with pools of blood, there was an electric fan still on, and there was blood everywhere on the sheets, quilts, slippers, and walls, and there was not even a place to put your feet.

Shao Dong surveyed the scene and found no traces of the struggle, but found two slash marks on the quilt at the scene, and a wallet and a mobile phone were found under the quilt.

There were ID cards and several cards in the wallet, no cash was found, there was a fruit knife on the table in the bedroom, there was no blood on the knife, and there were no signs of breaking the door lock in the bedroom.

Li Tie examined the corpse outside the house, rummaging through the pockets of his whole body, all of which were empty.

Wang Bo checked the wardrobes, under the bed, and in the drawers of the table in the house, little by little, and found no traces of turning.

Wu Wei extracted the footprints of the deceased's bare feet and compared the footprints at the scene in detail, which took a long time to completely compare due to the messy bloody footprints at the scene.

Two hours later, the group met to analyze the case.

Li Tie said to Wu Wei: "Let me tell you about the results of the preliminary autopsy. ”

"I have probed the liver temperature, the time of death is more than 24 hours, today is the 28th, the time of death is between the night of the 26th and the morning of the 27th, the cause of death is three stabs in the back of the neck, resulting in the rupture of the large artery, the murder weapon should be a sharp knife or dagger or the like. Judging from the situation at the scene, there were no traces of fierce fighting, and no traces of struggle were found at the location where the deceased fell to the ground, the deceased should have been attacked by the murderer from behind in an unsuspecting situation, or while asleep, and did not die immediately after being seriously injured, but chased the murderer all the way to the hospital, and finally died in the hospital due to excessive blood loss. Wu Wei introduced.

Shao Dong said: "From the investigation of the bedroom, no signs of rummaging were found, but there was no cash in the deceased's wallet, and the possibility of murder for money cannot be ruled out." ”

"The door lock of the bedroom is intact, the cabinets and drawers in the whole residence are neatly arranged, and the large wardrobe found with a passbook and more than 2,000 cash, and there is no trace of rummaging anywhere. Wang Bo added.

"The deadbolt of the door is intact, and the lock on the bedroom door is also intact, so where did the murderer enter?" asked Li Tie.

"During the survey, I noticed that there was a crack in the bedroom window, and I could immediately survey the area around the window. Shao Dong said.

"Let's go and have a look. Li Tie said.

When everyone came to the bedroom, Shao Dong took a magnifying glass to carefully observe the marks on the window, which was made of wood and painted with a thin layer of blue paint.

There was a fine layer of ash on the window frame, and on the inside of the window, two traces of suspected fingerprints were found.

"Found out?" asked Wang Bo on the side.

"Probably so, wait until I test it with the powder manifestation method. Shao Dong said and took out the tools from the survey box.

Powder visualization method - select metal or non-metal powder with large contrast with the color of the surface of the object, and use the fingerprint with low adhesion to turn the colorless fingerprint into a colored fingerprint with a layer.

Shao Dong dipped a little powder with a soft brush, gently flicked the handle of the brush, so that the powder was evenly scattered on the window frame suspected of fingerprints, and then gently brushed off the excess powder with the tip of the brush, and the fingerprints gradually appeared.

"It's done. Shao Dong said, using a piece of flat transparent adhesive tape to stick it on the fingerprint to prevent wrinkling and blistering, and then carefully peeled off the adhesive tape from one end, and then pasted it on a piece of paper that contrasted with the color of the fingerprint, and handed it to Li Tie.

This method of extracting fingerprints is the most widespread in criminal investigation and is characterized by its convenience. Commonly used powders include aluminum powder, iron powder, copper powder, graphite powder, etc.

Later, fingerprint extraction technology was developed, and it was also possible to use a magnetic fingerprint brush, made with a permanent magnet, using iron powder or a powder containing iron ore powder. To operate, sprinkle the powder evenly on the fingerprint, and then use a magnetic fingerprint brush to absorb the excess powder. The advantage of using a magnetic fingerprint brush is that it can avoid the detrimental effect of the brush on the fingerprint detail features.

"These two fingerprints should have been left by the suspect when he climbed the window, looking at the traces of the fingerprints, the distance is relatively close, and they were left by two adjacent fingers, so these two fingerprints should be from the same person. Li Tie looked at the fingerprint analysis and said.

Shao Dong thought for a moment and said, "Team Li, since the suspect is likely to enter the murder through the window, let's go outside the windowsill and see if there are any traces left by the suspect." ”

"Well, as I thought. Wang Bo said.

The group went outside and found an incomplete cloth footprint on the windowsill.

Cloth footprints belong to the footprints without texture, and the footprints left by shoes generally have a certain texture or regular pattern, while the cloth footprints are likely to be used by the suspect to camouflage, or the footprints left by wearing cloth or socks on the shoes.

"The suspect has some experience in counter-reconnaissance. The footprints on the scene are too scattered, we continue to search, as long as it is not a barefoot footprint, it is a clue, and everyone goes separately. Li Tie said.

In the living room, Wu Wei found three incomplete cloth footprints and a wavy blood footprint.

Shao Dong and Wang Bo found two suspicious incomplete footprints in the courtyard, one of which was similar to the cloth footprint on the windowsill, and there were three such footprints.

The other is a wavy footprint, but none of them are complete.

In the mud under the fruit trees on the west side of the yard, a relatively complete wavy footprint was found, this footprint was very deep, as if it had been stepped on by gravity.

This kind of footprint is called a three-dimensional footprint, and the height and body shape of the suspect can be judged according to the length and width of the footprint, and the production process of the shoe can be judged according to the characteristics of the wavy pattern, so as to narrow down the scope of investigation.

From the fence, I found the scratches of climbing, the courtyard wall is more than two meters high, and it is impossible for normal people to climb over the wall to enter.

The footprints left by half a shoe were also found on the wall, with a corrugated pattern on it, which is very similar to the corrugated footprints found indoors, from the perspective of footprints, the toes are in the direction of the courtyard, and after trace analysis, the three-dimensional footprints left in the mud floor in the courtyard are likely to be left by the suspect after jumping over the wall.

Wu Wei put a scale on all the suspicious footprints at the scene and began to take photos one by one to collect evidence.

Then, Wang Bo used the "gypsum molding method" to extract and fix the three-dimensional footprints.

In the on-site investigation, the Ministry of Public Security promoted the application of the rapid extraction method of criminal investigation gypsum molding, and selected gypsum powder with strong coagulation and dry and delicate powder to make the model with accurate shape, which can really, obviously and intuitively reflect the various characteristics of footprints.

Wang Bo first made a 2-4 cm high wall around the footprint, and gently poured the adjusted gypsum slurry with a ratio of about 5:3 to water from the lower part of the footprint. When the gypsum slurry is about 1 cm, put a thin wooden stick as a skeleton and continue to pour it. After the plaster has solidified, it is removed and rinsed with water to dry.

Shao Dong found a cigarette butt that he had smoked a few puffs under the tree in the courtyard and put it in the physical evidence bag.

After the on-site investigation was completed, everyone began to summarize and analyze.

Wu Wei said: "Generally, this kind of murder in the village is nothing more than vendetta killing, love killing, murder for money, judging from the situation at the scene, the murderer's approach is very cruel, no cash was found from the scene, and a person will certainly not be without a little cash as long as he lives, which shows that the murderer took the cash from the victim's family." ”

Li Tie was puzzled: "Through the analysis of the footprints left at the scene, the murderers should be two people, but what puzzles me the most is why one person is disguised on his shoes, while the other is not?"

Shao Dong added: "No murder weapon was found at the scene, just imagine, in the middle of the night, two people with knives climbed over the fence more than two meters high, burglarized and killed people, which is basically certain that the murderer is a young man." ”

Wu Wei introduced: "By measuring the complete three-dimensional footprint, it is 285 centimeters long, 85 centimeters wide at the front, 64 centimeters wide at the back, and the size of the shoe is 42 yards. I have made a rough portrayal of one of the suspects for your reference: the murderer is about 25 to 40 years old, about 1.75 meters tall, and has a medium physique. The other suspect was unable to obtain further information due to the camouflage on his feet. ”

Li Tie looked at his watch, it was already more than eight o'clock in the evening, and said to Wu Wei: "You take Li You's body and hurry back for further autopsy, let Xiaodong drive you, Xiaobo and I won't leave, we are going to investigate overnight, we will investigate around the hospital to see if there are any suspicious clues, the road conditions are not very good, Xiaodong, you must pay attention to safety." Rush back early tomorrow morning. ”

"Okay, Team Wu, I understand. Shao Dong replied. Real lady online service, help you find books to chat with you, please micro / letter / search / search hot network article or rd444 waiting for you to tease~