How does a primary school student burn down the school dormitory he hates at home?
How can a laid-off worker set fire to goods in a factory or warehouse in another field?
Among all kinds of crimes, arson and murder are serious crimes that are often mentioned in the same breath. Some criminals who think they are smart will use remote control ignition or delayed ignition. Although the fire will destroy some crime evidence, they underestimate the police's ability.
Detective capabilities are often self-defeating.
Zhang Qingjin hung on a hook on the bedroom roof, which was reserved for the ceiling fan.
Under Zhang Qingjin's drooping body was a bed, which was beyond recognition after being burned. His lower body was charred into a black charcoal shape, his coat was shrunk into a ball and attached to his body like a tree tumor, and his facial skin burst, charred on the outside and tender on the inside.
, like roast lamb in a restaurant.
Many people who commit suicide are worried that they will not die, so they often choose multiple suicide methods at the same time.
For example, drink pesticide first and then hang yourself, take a large amount of sleeping pills and then jump off the building.
The police found the crime tool-a cutting machine in the storage room of Zhang Qingjin's rental house. This directly pointed to him as the murderer. Zhang Qingjin killed Lin June and her son Xiao Tiyu, and committed suicide in fear of crime. He first set a fire and then hanged himself.
On the surface, it seems that this person is determined to die. The truth of the case has been revealed and it should be over.
However, this fire raised a lot of doubts.
Fire scenes vary widely. The most important thing in the investigation process is the fire scene investigation. Since the fire forms are different and the physical and chemical properties of the original items that form trace evidence are different, the causes of fires are also diverse. First, the fire point must be determined based on the on-site investigation.
, any remaining objects in the center of the fire are crucial. Furniture with small supporting surfaces such as round tables and coffee tables will fall in the opposite direction to ordinary furniture due to the weight loss of the side that burned first under the action of the flame. The ashes of wooden furniture will pile up vertically.
Although it cannot indicate the direction of the fire's spread at its original location, it can prove the extent of the fire's development and the distance from the fire point, so that the location of the fire can be determined based on the spread traces.
Bao Zhan found a pile of burning materials beside the bed. Based on the scene, he confirmed that this was the point of fire. He separated the burning materials into a cross-section, carefully observed the burning conditions of each layer of the residue, and identified the type of material in each layer.
Found the cause of the fire.
There are residual mosquito-repellent incense, deformed and bent mosquito-repellent incense holders, match stems, and newspaper ashes in the burning materials. By connecting these things, you can analyze how the fire occurred.
The murderer lit a plate of mosquito-repellent incense and placed it on the stand, placed a few matches on the mosquito-repellent incense, and then placed a ball of newspaper on top. The mosquito-repellent incense ignited the match, which burned the newspaper, and the bed sheets next to it also caught fire, and a fire broke out.
Mosquito-repellent incense can burn for several hours and can provide the killer with proof of alibi.
When the fire broke out, the murderer was far away from the scene, deliberately misleading the police into thinking that the murderer had no time to commit the crime.
After interviews, it was found that Zhang Qingjin had bought mosquito coils and matches from a nearby canteen. The forensic doctor's autopsy report did not find any smoke in Zhang Qingjin's trachea and lungs, indicating that he was already dead when the fire broke out.
The murderer possesses the characteristics of a highly intelligent criminal and fabricated a suicide scene using local materials within a short period of time after the murder.
Although there are many clues, the case is still at a deadlock, and the police are at a loss to solve it.
The special case team held an emergency meeting. At the meeting, everyone confirmed the direction of the investigation. The two human pig cases were committed by acquaintances. At the time of the incident, Lin June took the child with her, and also put on makeup and lipstick.
She was going to meet a very close person.
A leader said: "Why is the case
No progress? Now we don’t even know who the murderers are, whether they are men or women.”
Su Mei said: "I prefer that multiple women commit the crime. Now that there is one more suspect, the case is still making progress."
The leader asked: "Which one?"
Su Mei said: "Zhang Qingjin's wife, a good family was broken up because of an extramarital affair. Zhang Qingjin's wife may have a grudge against Lin June and seek revenge."
Bao Zhan said: "I think the murderer is a male and he committed the crime alone."
Hualong said: "I agree with Baozi. None of the victims had obvious fighting scars. The murderer should be a strong adult male with a high IQ and excellent physical fitness."
Erbao stood up and said, "I want to reflect on it. I concealed something important."
The leader asked: "What is it? Sit down and talk about it."
Erbao still stood and said: "That day, Aunt Qi molested me. After I went home and washed off the lipstick marks on my face, I suddenly remembered that there were lipstick marks on the bodies of Lin Liuyue and Xiao Tieyu. This
Is there any connection?"
Hualong said: "If you say this, Aunt Qi's suspicion cannot be completely ruled out. If you ask her to molest her again, we will compare the ingredients of the lipstick."
Erbao looked embarrassed and said hesitantly: "I...Okay!"
The leader said: "Stop joking, what should we do now?"
Professor Liang said: "I have a good idea!"
The leader said: "What can we do?"
Professor Liang said: "There must have been some omissions in our early work, so that no important clues were found. If we want to find a breakthrough and identify the real culprit, we will do the boring and cumbersome work again in the stupidest way!"
"
Professor Liang redistributed tasks and asked everyone to take their own responsibilities, which must be comprehensive and in-depth.
Erbao visited Aunt Qi again to thoroughly find out whether this person was suspected of committing the crime.
Su Mei conducted a focused investigation on Zhang Qingjin’s wife and immediate family members.
Hua Long learned about the social relationship of Zhuang Qin's lover Xiao Ming from the side, and whether there were other men besides Zhuang Qin.
Bao Zhan went to the provincial capital to make a comprehensive record of Zhuang Qin's whereabouts during the time of the crime, including the people he had close contact with, and a list of everyone he had come into contact with. The possibility of paying someone to kill someone could not be ruled out at the moment.
Zhang Qingjin’s wife is also a teacher, and the couple teaches in the same middle school.
After the divorce, she returned home alone and closed the door alone. The house was in a mess, the drawers were pulled open, the cabinets were open, and the food in the kitchen smelled rancid. She sat on the ground against the wall in the dark.
, my heart was filled with sadness.
Su Mei and two policemen knocked on the door and entered. The policemen wanted to take Zhang Qingjin's wife back to the police station, but Su Mei stopped her.
Su Mei saw a pair of crutches placed by the wall. Zhang Qingjin's wife was a disabled person. Her right lower limb was paralyzed due to illness, which directly ruled out her suspicion of committing the crime.
The police implicitly explained their purpose, saying that something had happened to Zhang Qingjin and that there was a fire at his residence.
Zhang Qingjin's wife stood up tremblingly and asked: "Which hospital is he in? I'll go see him."
Su Mei said: "I'm sorry...your husband has passed away."
Zhang Qingjin's wife was in a trance and fainted to the ground.
Two families were torn apart, three people were killed, but the real murderer is still at large, hiding behind layers of fog.
Professor Liang believed that Zhuang Qin was the most suspicious, so he sent his capable general Bao Zhan. Bao Zhan felt a lot of pressure. After arriving in the provincial capital, he didn't sleep a wink for two days and two nights and visited successively.
Zhuang Qin contacted everyone, investigated every place Zhuang Qin visited, and obtained photos of Zhuang Qin at the dealership and surveillance footage of his hotel stay. After repeated comparison and analysis, he made a surprising discovery.
On the train returning, Bao Zhan fell into a deep sleep. At the same time, Hua Long and his men arrested Zhuang Qin.
This interrogation was different from previous police summons. Professor Liang was proficient in criminal psychology and knew that the suspect's psychological quality was very good, so he set up a special interrogation room.
The interrogation room is soundproofed from the outside world, and there is a see-through mirror on the wall. Most suspects are already very nervous when they are handcuffed, and the mirror deepens their uneasiness. The suspects do not know who is behind the mirror, and are worried that there may be someone standing behind the mirror.
Victims or witnesses, driven by this idea, the police will have a great psychological deterrent effect on the suspect.
This interrogation room is closed, with no sunlight. The criminal suspect and the police are separated by a cold iron fence, which makes the police appear more majestic. The light shines on the suspect's face, and no expression can escape the police's eyes.
This intensified the atmosphere of fear and intimidation. No one would want to stay in this place for too long.
The interrogation officially began. Professor Liang also put on his police uniform and stared at Zhuang Qin intently.
Zhuang Qin said uneasily: "I want to find a lawyer, why should you arrest me?"
Professor Liang said: "Of course, you can find a lawyer to defend you in court. This is your right."
Hua Long slammed the table, pointed at Zhuang Qin and shouted: "I'm arresting you knowingly. You know why I arrested you here."
Zhuang Qin said: "I don't know, don't set a trap for me."
Professor Liang said: "Zhang Qingjin, do you know him? He is the man who had an extramarital affair with your wife. He is dead."
Zhuang Qin said: "What does this have to do with me?"
Professor Liang said: "Of course it has something to do with you. You know he is dead, right?"
Zhuang Qin said: "I heard that he was burned to death."
Professor Liang said: "Where were you when the fire broke out?"
Zhuang Qin said: "I don't know when the fire broke out. I have been at home with a few relatives to take care of my wife's funeral."
Hua Long said: "You pushed it quite cleanly. I think you won't tell the truth without beating you up."
Zhuang Qin said: "Are you still engaging in torture to extract confessions?"
Professor Liang said: "We will be very polite to you. Don't worry. You were attending a sales meeting in the provincial capital and your wife was killed. On the surface, you didn't have time to commit the crime. However, we found a few minor problems. Please tell the truth."
answer."
Zhuang Qin said: "Can I let my lawyer answer?"
Professor Liang looked at Zhuang Qin, was silent for a while, and said, "If you don't answer, you feel guilty. What are you trying to hide?"
Zhuang Qin said: "Okay, then you can ask."
Professor Liang said: "You usually smoke Yuxi cigarettes that cost 20 yuan a pack. Why do you smoke Honghe cigarettes that cost 5 yuan a pack in the provincial capital?"
Zhuang Qin replied: "Isn't it okay if I save money? What's the problem?!"
Professor Liang said: "You rarely eat garlic and you can't eat spicy food because you have a gastric ulcer. But in a restaurant in the provincial capital, you ordered a plate of spicy chicken and a portion of garlic eggplant. Why is this?"
Zhuang Qin became a little angry and said: "I am free to eat whatever I want. You have too much control."
Hua Long said: "Keep pretending, you are really good at pretending."
Zhuang Qin turned his head to one side and said, "If you don't have any evidence, you can detain me for up to 48 hours."
Professor Liang said: "Do you know who is behind the mirror?"