Serious Crime Unit 1

Chapter 1202 Revenge (11)
After Zhou Ting finished taking pictures, Wu Jiang said to Jiang Yiming: "There is no way out despite the mountains and rivers, and there is a bright future in another village. Team Jiang, we have found a clue."

"Clue? What clue?" Jiang Yiming asked doubtfully.

“When we went to Yezhigu Valley to investigate the site for the second time, we extracted 5 types of shoe prints, one of which was very similar to the shoe prints on the floor in front of Ning Zhiwu’s door. After comparison, it was confirmed that the shoe prints in Yezhu Valley were Ning Zhiwu’s, then we can conduct an in-depth investigation on him, and it’s best to search his home. Maybe the suspected pair of shoes is still on the shoe rack at his home.”

"Old Wu, you are indeed our treasure. Why didn't I think of that?" Jiang Yiming patted him on the shoulder and praised him happily.

"'A wise man will always lose something, and a fool will always gain something.' You worry too much. I am more Buddhist and like to work slowly and carefully. Maybe I am getting old."

"Not old, not old. You are only 52 years old. Li Changyu only officially retired at the age of 69. After you retire, we will hire you back as a consultant." Wu Jiang smiled. He felt that the passage of time is the most saddening thing. Fame and fortune It was as light as a feather to him.

After Wu Jiang returned to the team, he compared the two shoe prints. Although the patterns of the shoe prints were different, the gait of one of the shoe prints extracted from the scene was completely consistent with the gait of the shoe prints extracted from Ning Zhiwu's door.In other words, Ning Zhiwu had been to the crime scene, but his shoe prints were about 100 meters away from where the body was found.

Because the 100 meters of shoe prints from the corpse burial place to Ning Zhiwu’s shoe prints were destroyed by students from the kindergarten class, and Ning Zhiwu said that his student Xiao Yan was from the kindergarten class, and he most likely knew Mingyan. Then she instigated Mingyan to take the students to the crime scene for a picnic. If so, Ning Zhiwu's criminal IQ was terrifyingly high.

Jiang Yiming called to ask Mingyan if she knew Ning Zhiwu?Mingyan said she knew him because Ning Zhiwu occasionally came to their school to give lectures, so she had known Ning Zhiwu for three years.Moreover, it was Ning Zhiwu who told her: The marigolds in Wild Boar Valley were blooming extremely brightly and were more beautiful than heaven. She would not be disappointed if she was asked to take her students there for a picnic when she had time.I didn't expect Ning Zhiwu to be so thoughtful... But how did Ning Zhiwu know that Liu Dayu would definitely take Zeng Xiaoyi to the crime scene that day?

Jiang Yiming and Zhou Ting went to Fenghua Community and copied all the surveillance videos captured by the monitors, and asked the visual inspection team to work overtime to check.Although there are monitoring blind spots in Fenghua Community, it is impossible for Ning Zhiwu to avoid all monitors. After all, the property management company will not let anyone enter the monitoring room casually.

Jiang Yiming went to Fang Lihua's office to issue a search warrant. After obtaining the search warrant, he called Wu Jiang, Xiao Ke, Lu Yingying, and Zhou Ting to search Ning Zhiwu's house.After Ning Zhiwu opened the door and saw them, he was very calm and asked softly: "What happened that requires you to mobilize forces like this?"

"We suspect that you killed Liu Dayu, and now we are going to search your home. This is the search warrant, please take a look." Zhou Ting took the search warrant and showed it to him.

"Yes! You can search whatever you want." He replied with a smile.

Lu Yingying asked him to open the computer in the study room, so he started the computer, entered the password, and opened it for Lu Yingying to check.Lu Yingying first checked his online browsing records, but all the online browsing records were cleared by Ning Zhiwu.Of course this was not a problem for Lu Yingying, she used software to restore it.However, over the past year, he had too many online browsing records, and it was impossible to find out whether he had purchased tetrodotoxin online. Lu Yingying asked to take his laptop away, and he agreed.

Wu Jiang inspected the shoes on Ning Zhiwu's shoe rack. There were a total of 6 pairs of leather shoes and 4 pairs of sports shoes, all of which were Nike brand. The shoe prints extracted at the crime scene were sports shoes, so he only inspected four pairs. Checking the sneakers, one pair of Nike shoe prints produced in 2019 were exactly the same as the shoe prints extracted at the scene.

Wu Jiang put the shoes into the evidence bag, which could prove that Ning Zhiwu had been to the scene, but it could not prove that he poisoned Liu Dayu.

At this time, Jiang Yiming's mobile phone received a surveillance video from Wen Xiaorou. She left a message on WeChat explaining: This is the surveillance video of Ning Zhiwu sneaking out of the north gate of Fenghua Community at 3:29 pm on March 6.

Wen Xiaorou then sent another surveillance video, which showed that Ning Zhiwu, wearing a large mask and a peaked cap, returned to the community from the north gate at 2:28 a.m. on February 5.He was wearing a black Nike sportswear, and his gait was a little weak, maybe because he was tired from climbing the mountain.

Jiang Yiming thought: Just because Ning Zhiwu went to the scene of the crime at the time of the crime, he could not be convicted, because he could say that he went hunting in the Wild Boar Valley at that time.There are no suspicious biological samples in Liu Dayu's fingernails, and there is no physical evidence such as clothing fibers. What should I do?
If Ning Zhiwu has tetrodotoxin in his body, then it is a relatively reliable evidence.After Jiang Yiming watched the surveillance video on his mobile phone, he calmly said to Ning Zhiwu: "According to our investigation, you have a set of black Nike sneakers. Where do you put them?"

"Oh, put it in the closet in the bedroom." He sat on the sofa and pointed to the bedroom door.

Jiang Yiming walked into the bedroom, opened the closet, and saw the Nike sportswear he had worn. He put the sportswear into the evidence bag.They then conducted a blanket search of Ning Zhiwu's home, but did not find the key evidence they wanted: tetrodotoxin.

"Ning Zhiwu, please come with us to the Municipal Bureau's Criminal Police Team. We suspect that you killed Liu Dayu and need your cooperation in the investigation." Jiang Yiming said to Ning Zhiwu. "Why do you suspect that I killed him?" He still asked without shame or annoyance, with a relaxed tone.

"First, we extracted the suspect's shoe prints from the scene, which were exactly the same as the Nike shoe prints on your shoe rack. Second, you said you were working at home at the time of the crime, but we checked the North Fenghua Community The surveillance video of the door shows that you walked out of the north gate at 3:29 in the evening on March 6, and returned to Fenghua Community at 10:2 in the morning on February 28. You are completely lying." Jiang Yiming looked at it coldly. Looking at him.

"This can only mean that I went to Wild Boar Valley at that time. Why do you suspect me of murder?"

"Based on the above two points, we have the right to summon you to cooperate with us. Let's go."

"Just leave. I believe that the procuratorate and the court will not sentence me just because I have been to Wild Boar Valley." He tossed his hair coolly and walked out of his house. Of course, he did not expect that he would never be able to go back again. Home.

Jiang Yiming handed Ning Zhiwu's sneakers and sportswear to Luo Jin and said, "Both the sneakers and sportswear have been washed by Ning Zhiwu. Can it be detected if tetrodotoxin remains on them?"

"No problem. As long as there is tetrodotoxin dripped on it, even if it is diluted 10 times with water, the toxin can be detected with a mass spectrometer. Pesticide residue detection is a good example. There is also a Luma detector that can detect tetrodotoxin diluted 10 times. Ten thousand times more blood, body fluids, semen, and brain tissue." Luo Jin said confidently. He is the director of the laboratory, so of course he understands the power of the mass spectrometer.

More than 1919 years have passed since the advent of the mass spectrometer in 100. It has been commonly used in geology, semiconductors, medicine, petrochemicals, food and pharmaceuticals, etc. In the past 30 years, it has also been commonly used in criminal investigation technology to analyze trace evidence. It can quickly analyze substances. And accurate analysis makes the physical evidence more scientific and rigorous.

Luo Jin soon discovered a trace amount of tetrodotoxin in Ning Zhiwu's sweatpants. This may have been accidentally contaminated by Ning Zhiwu when he was packing tetrodotoxin.There was another surprising thing: Luo Jin actually found a sperm spot on the right cuff of Ning Zhiwu's sportswear.

Luo Jin speculated that when Liu Dayu and Zeng Xiaoyi went to get condoms after completing the transaction, their fingers accidentally got their own semen, and then when they pulled with Ning Zhiwu, the wet semen got on his cuffs.Luo Jin compared the DNA of the semen with that of Liu Dayu. The result was that the similarity rate between the two was 99.99%. It can be concluded that Ning Zhiwu was the murderer of Liu Dayu.

At the same time, Lu Yingying discovered on Ning Zhiwu’s computer that he had purchased 10 ml of tetrodotoxin on a website called Se Se Dou. This is a pornographic website, also called the Deep Web. Because the server is abroad, it is impossible to retrieve it from the source. After each eradication, it will automatically appear on the computers or mobile phones of past viewers.

Ning Zhiwu only used 5 ml of tetrodotoxin. I wonder if he threw away the other 5 ml?The tetrodotoxin on Ning Zhiwu's sweatpants must have been accidentally picked up when he was packing.Lu Yingying also discovered that Ning Zhiwu used Alipay to pay for tetrodotoxin.

Lu Yingying reported the situation to Jiang Yiming. Jiang Yiming thought for a while, called Liu Xiaowei and asked him to take people to check the store selling tetrodotoxin. Liu Xiaowei happened to have no case, so he happily agreed.

With Ning Zhiwu’s record of purchasing tetrodotoxin, the tetrodotoxin on his sweatpants, Liu Dayu’s semen on his cuffs, the shoe prints outside the crime scene, Mingyan’s testimony, and the surveillance video of the north gate of Fenghua Community... these are complete. The chain of evidence allows Ning Zhiwu to be interrogated.

So Jiang Yiming called Wu Jiang and Lu Yingying to interrogate Ning Zhiwu.They thought that criminals with high IQs like Ning Zhiwu would be difficult to deal with, but they didn't expect that when Jiang Yiming put the evidence in front of him one by one, he would admit it frankly.

However, he did not admit that he poisoned Liu Dayu, but that Liu Dayu poisoned himself.

"Poison yourself to death, and no one will believe you!" Jiang Yiming didn't expect him to say such words.

"It's true. My friend Huo Song and I filmed the process of Liu Dayu poisoning himself with an infrared camera. The video is saved on my mobile phone. You can take a look. After watching it, I believe you won't think I killed him," he said, pointing to his pocket.

(End of this chapter)