National Forensic Doctor

When Jiang Yuan and Miao Ruixiang arrived at the scene, people from the Criminal Division Center had almost arrived.

Niudong, the own forensic doctor in the advance area, was also called over. He has a short and stocky body and can't open his eyes.

"Captain Jiang arrived first." Niudong yawned tiredly and said quickly: "I'm sorry, since I started catching these two-flying chickens, I've been going everywhere to collect physical evidence."

A popular forensic knowledge, biological test materials related to the human body are forensic evidence. In other words, when a piece of toilet paper is white and tender, it is a general evidence, but if it is stained with human tissue, whether it is nasal mucus, blood, Milk, saliva or something else, it instantly becomes forensic evidence, and it becomes Niudong's area of ​​expertise.

Jiang Yuan smiled and nodded to Niudong and said, "I was looking at the corpse, but I was called over. Let's go in first."

"Okay, you go first..." Niudong had done many cases with Jiang Yuan before, and he and Jiang Yuan were considered familiar.

Several people filed in.

The scene was an ordinary apartment of about 80 square meters, with two bedrooms and one living room, which was neatly packed.

The suspect was sitting on the sofa with his hands behind his back. His arms had thin muscle lines. He was very beautiful, but his face was too square, his skin was rough, his expression was arrogant, and his demeanor was slightly crazy.

Boom.

A criminal policeman brought out a courier box and placed it in the center of the living room. He said, "They are all condoms, from the same brand."

"You really won't get tired of buying so many of the same brand." Lei Xin deliberately stimulated him to speak.

The suspect had some counter-reconnaissance experience and found that something was not right, but he was still full of hope and said nonchalantly: "You don't care how many condoms I use?"

"Zhu Tianwei, do you have a girlfriend?" Lei Xin asked.

The suspect Zhu Tianwei was stunned for a moment and said, "Are you in charge?"

Lei Xin curled his lips and said, "You bring condoms to go to prostitutes, right?"

Upon hearing the word "prostitution," the suspect's face visibly improved, and his voice became louder: "You are too lenient. Are you saying that I am a prostitute? Do you have any evidence? So you broke into the house."

Lei Xin then looked at Dr. Niu.

He wanted to conduct a surprise interrogation of the suspect. The physical evidence at the scene of this case was extremely damaged, and the DNA and fingerprints of the murderer could not be directly identified. At this time, it is very important to obtain the suspect's confession. Equally important is Gather evidence through the suspect's confession.

There are many methods of surprise interrogation. Some people like to use a thunder strike to take advantage of the suspect's uneasy state to obtain as many confessions as possible when he has just been arrested.

Of course, you can also, like Lei Xin, conduct step-by-step and targeted inquiries to confirm the suspect's criminal facts, even if it is a crime in other fields, and use this to expand the results step by step.

Forensic doctor Niu got the hint from Lei Xin's eyes and immediately stepped forward to see the express box that the criminal policeman moved out.

With just one glance, Niudong laughed: "The one you bought is a small brand."

"How about a small brand? I can just play it myself and feel comfortable." Zhu Tianwei was a little unhappy.

Niudong chuckled, took out a box of covers with gloves on, looked at the ingredient list on the back, and said, "The one you bought has an unstable production environment and the production line is shared with other models. So, The lubricating oil used in each batch is slightly different, which is related to the cleaning done by the workers, the type of collinear model, and the quality of the raw materials in this batch."

Zhu Tianwei frowned upon hearing this.

Niudong said happily: "In short, if I take your condom and compare it with the condoms you used at the scene, I can prove that these are the same batch of condoms..."

"So what? I'm a prostitute, so what about you?" Zhu Tianwei didn't care about the 15-day administrative detention.

Niudong's proud expression couldn't help but froze, yes, everyone has admitted to prostitution, so what's the use of such an advanced certification process that costs several thousand yuan more?

Niudong's mood became depressed, and he actually lost his guard.

"Where did the money come from?" Lei Xin asked, quickly suppressing Zhu Tianwei's arrogant mood.

The muscles in Zhu Tianwei's arms swelled for a moment, then softened again, and he pursed his lips and remained silent.

"Don't think that if you don't ask, we won't find it. If you sell the stolen goods, there will be a way to sell the stolen goods, and there will be people to collect the stolen goods. Money has a route."

"There are so many places where you can get cash now. We can always find it if we check it. But if you save us some time, we can also make it easier for you."

Lei Xin continued to exert pressure and told the truth.

What domestic criminal investigators are most afraid of is not being able to find the person, and what they are most afraid of is not knowing who did it. As for the matter of finding evidence after finding the person, there is no poisonous tree in the country, nor does it strictly emphasize procedural justice, and it is not even easy to exclude evidence.

In short, the domestic judicial system pays more attention to the facts, including the presiding judge of the court. When asking questions, most of the purpose is to clarify the facts.

The purpose of Lei Xin's surprise interrogation now is also to find more evidence.

Proving prostitution, and even having the owner of the hardware store testify against the murderer, are all indirect evidence. Indirect evidence is not enough to convict a person of death. It will be photographed when it is sent for inspection.

Shen Yaowei, who had been paying attention to the backlog class here, saw Zhu Tianwei's muscles, and his nerves trembled violently, but it was not because of fear, but because he suddenly thought of a legend he had heard in the past two days.

Shen Yaowei's cousin is from the Changyang City Public Security Detachment, and there are various sources of information. Looking at Zhu Tianwei on the sofa, Shen Yaowei looked around, and whispered in the ear of Liu Wenkai, whom he liked better, "I heard them say that there is a rumor about this guy, do you know?"

"What rumors?" Liu Wenkai put down his phone.

Shen Yaowei said in a lower voice: "It is said that this guy is extremely powerful. Once, he made a woman lie on the bed, then picked up another woman on top, and alternated the output for 10 minutes."

Liu Wenkai's tongue was stiff when he heard this: "Cuddled for 10 minutes?"

"The woman didn't want to fold the arhat and asked for more money, so he just picked her up." Shen Yaowei paused and said, "Don't tell me, rich porters are really happy."

Liu Wenkai fantasized for a moment and nodded slowly: "But...if you really give the porter a good father, he will have to be carried away in three years at most."

"Three years are worth it." Shen Yaowei said, thumping his waist: "We haven't done much in the past three years, except catching thieves."

Liu Wenkai smiled contemptuously.

…

Lei Xin interrogated him on the spot and asked the technicians of the Criminal Division to start work, thereby continuing to increase the pressure on Zhu Tianwei.

Jiang Yuan put on gloves, head coverings and foot coverings, then asked someone to move a box of covers from the living room, and then he started searching.

The first thing he searched for was the shoes at the door. He looked through the soles and insides of the shoes, but found nothing. Then he went to rummage through the dirty clothes in the washing machine.

Liu Wenkai, who had been the de facto leader of the serious crime team for many years, knew it at a glance. He went over and asked Jiang Yuandao: "Do you want to find the clothes and shoes used when committing the crime? They should be discarded. Even if this guy is very economical, he is still a social university." graduated."

The two stayed in the bathroom and closed the door. The suspect outside could not hear their conversation.

"Not really. I just looked at his criminal record. Once he was detained for less than half a year, he was released, and once he was punished by public security, he only lasted seven days. He is a graduate of a social university at best." Jiang Yuan said while looking for something. .

Liu Wenkai was amused: "Do social universities also discriminate against academic qualifications? However, even if he graduates from a junior college, it is impossible for him to bring the bloody clothes back."

"I looked at his performance record when he was in school, and I feel that he is not a thorough and meticulous character. He used a lot of salt and detergent at the crime scene, which must have been a moment of quick wit."

"I agree with this. If he could know what was in the other person's home, he shouldn't rush into the house when the three people were there." Liu Wenkai said.

"So, regarding the bloody clothes, I guess he didn't bring his own clothes. He probably changed his clothes at the victim's home, and probably also changed his shoes." Liu Wenkai was stunned by Jiang Yuan's answer.

Jiang Yuan continued: "Although the scene was severely damaged, the blood loss of the three people was still very large. There should have been a lot of blood spattered on the murderer at that time. Therefore, he should have changed his clothes before going out. Clothes and shoes, otherwise they will leave traces outside the door.”

"Not taking a shower, just changing clothes?"

"Maybe it's because I'm afraid of leaving hair behind. I guess I've heard of similar cases." Jiang Yuan expressed regret. There are many cases of murderers bathing in the victim's home. Some of them were handled with care and nothing happened, but there are also some people who were arrested because their hair was left in places such as floor drains. Jiang Yuan once worked as an employee of a logistics company. The murderer might have been fine at first, but because he encountered Jiang Yuan's LV4 crime scene investigation, he became troublesome.

In short, for the police, the bathroom at the crime scene must be carefully investigated. More and more criminals are arrested for this purpose, and the experience of their predecessors is naturally spread more and more widely.

Jiang Yuan changed the topic and continued: "Although I don't know what the criminal did with the bloody clothes and shoes at the scene, there are still blood stains in the clothes and shoes he changed. Especially the shoes, the remaining blood on the body is likely to bleed. Go down. If this is an active case, we might lock it down before he has time to deal with these clothes!"

Liu Wenkai was stunned again, then smiled helplessly: "I thought..."

If another technician had said that, Liu Wenkai would have lost his temper, but Jiang Yuan's words...

Just listen to Jiang Yuan: "But..."

"kindness?"

"When I was just looking at the clothes and shoes, I suddenly discovered that some of the suspect's clothes were very cheap work clothes, but some of the clothes, especially the shoes, were actually quite good, and they were basically brand-name goods. Anta, Nike, Adidas, etc. It’s not a limited edition, but it’s not from Putian.”

Liu Wenkai frowned: "Does this mean the suspect's actual living standard is higher than that of ordinary porters?"

Jiang Yuan circled his fingers and said: "My family also has many houses for rent like this. It is an apartment building with more than 80 square meters and convenient transportation. The monthly rent is 2,000 yuan. Zhu Tianwei works as a porter. If you work on a piece-rate basis, you only earn three to four thousand a month most of the time. If you rent such an expensive house and have to eat and drink, how can you have the money to buy branded clothes?"

"Does he have other sources of income?"

"It's very possible. The profession of porter is very convenient for home invasion and crime."