novice forensic medicine

Chapter 58
Zhou Ning laughed twice, such an abrupt movement made the two people confused.

"The hardness of the human skull is between 3-4, and the hardness of natural marble is between 3.5-5.5. I can't find a suitable stone, so let's use this to simulate it.

Experiment with three movements: horizontal hitting with both hands, vertical hitting with one hand, and vertical hitting with both hands, and then compare the marks of the marble being crushed, so that you can intuitively understand how the murderer injured the dead. "

Xu Dayuan nodded.

"The experiment is fine, but why did you give me the marble?"

"I'm too tall, it's not easy to lift up and hit."

Da Zhao didn't think it was a big deal, he leaned over and handed the wrench to Zhou Ning with his teeth bared.

"It's okay, I'm short, you come and smash it."

Zhou Ning rolled his eyes.

"I'm bored, let's do an experiment quickly."

Da Zhao stopped talking nonsense, wearing goggles, and raised a wrench with both hands sideways.

"Boss, if you are ready, I will come!"

"Aim and hit me on the head."

Da Zhao trembled, with a bitter expression on his face.

"Boss, don't scare me, I'm here."

As he said that, Da Zhao swung his wrench horizontally and smashed it towards the marble slab. The marble slab was smashed and splashed some debris, but it was not broken. Xu Dayuan also turned over the stone slab and looked at it. He could feel Da Zhao's hand on his hand. The strength is not broken, which is a bit unexpected.

"It didn't break?"

Zhou Ning nodded, marked a 1 on the marble board with a marker, and then signaled to change to the second one. This time Xu Dayuan held his hands horizontally, and Da Zhao held a wrench in one hand and smashed it down.

With a bang, the marble slab exploded obliquely, and a lot of gravel was splashed like the point of force, and the cracks also appeared obliquely along the point of force, Xu Dayuan looked at it.

"This piece of marble has cracks. The next time you smash it, avoid the brownish-red pattern, and smash the white here, and come again."

Zhou Ning quickly went to mark it, and then moved out of the way. For the third time, Da Zhao held the wrench in both hands and smashed it down from top to bottom.

This time, the marble slab was not cracked, and the wrench was completely inlaid on the marble slab. Zhao Xinli spent some effort shaking before pulling out the wrench. The broken part was indeed in the same shape as the head of the wrench, a round C shape. A dent appeared, but the shattering was severe, obviously the murderer was not as strong as Da Zhao.

"It seems that Xiao Zhou's forensic analysis is correct. The murderer hit the dead man vertically with a wrench when he lowered his head."

"I don't understand. Dressed like this and it's so cold outside, how can the deceased squat down obediently, without attracting her attention, and smash the deceased's head?"

Xu Dayuan was silent, Zhou Ning pursed his lips, looked at the wrench and the defect on the marble, rushed back to the dissecting table, restored the dead man's scalp, and stared at the defect.

"The murderer hit the dead with all his strength, but his strength was not as strong as that of Da Zhao, but there is also a problem, just like Da Zhao's action just now, when he smashed the wrench, it would be stuck on the head of the dead. If he wanted to pull out the wrench, he would How to do it?"

Da Zhao scratched his head, held Xu Dayuan's shoulder with one hand, and kept shaking behind his head with the other.

"Press your shoulder or head, shake it and pull it out."

Xu Dayuan nodded accordingly, he thought so too, but his eyes widened instantly.

"You mean clothes, there will be residues on the clothes of the deceased? I remember that the test report said that a male DNA that did not belong to the deceased was found in the extracts from the deceased's wounds?"

Zhou Ning smiled. It seems that people's subconscious actions are similar. He walked directly towards the evidence bag of the deceased's clothes, unfolded it, and laid it flat on the stainless steel table. He searched and said.

"The unknown male's DNA, I judged to be blood, the murderer had wounds on his hands, combined with the scratches on the deceased's nose and brow bone, I suspect that the deceased had an argument with the murderer, the deceased injured the murderer, and then the deceased was pushed down, and the deceased was about to crawl When he got up, the killer hit the dead man's head from behind."

As Zhou Ning said, he looked at the nails of the deceased. He had seen the nails of the deceased during the autopsy. They were cut very short, and they were bald. Think about it, but looking at it now, maybe it's not the reason.

Pull over the LED magnifying glass light and carefully observe the fingertips. The traces of nail trimming are very neat. It is not done with nail clippers around the edge of the nail a few times, but directly cut bald.

Zhou Ning waved at Da Zhao.

"Get me the luminol spray and spray it on the dead man's nails!"

"After soaking in the water for so long, what blood remains?"

Even though he said this, he didn't stop moving. He found the luminol spray, brought it to Zhou Ning's side, and carefully sprayed it in a circle. On both sides of the edge of the dead man's nails, a faint blue-green fluorescence could be seen.

Xu Dayuan also came over. After all, he has been handling cases for many years and has a lot of experience. Seeing this, he immediately reacted.

"The deceased scratched the murderer, and the murderer has excellent anti-reconnaissance capabilities, so even when throwing the corpse, he did not forget to cut off the nails of the deceased to eliminate all possible traces?"

Zhou Ning nodded.

"I think we can search the reservoir carefully. The murder weapon may be found within 20 meters from the shore. He will not take this away. Moreover, the murderer's home should be in the opposite direction from the Baima River Reservoir. After all, we always say throw it away. near buried."

Xu Dayuan took out his mobile phone and walked to the side to make a call.

Zhou Ning moved the LED magnifying glass light to the clothes of the deceased, and observed the two shoulders on the back of the clothes inch by inch. When he searched for the right shoulder, there were three glued things in the opposite direction. I don't know what kind of substance it is. After touching it with gloves, it is still a little sticky and seems a little reflective.

Soaked in water for so long, can it still be sticky? Is it glue?
Da Zhao snorted, hurried over, thought for a while and said.

"This is fluorescent paint."

Zhou Ning looked at Da Zhao in puzzlement. He didn't understand these things, and he didn't seem to notice where this thing was used. Da Zhao quickly continued.

"When the headlights are on at high speed, there is a reflective strip on the median strip, which is a kind of fluorescent paint. Of course, some dance halls and discos also use this. This thing dries faster than ordinary paint, but it probably disappears after soaking in water. As a result, the clothes are dry, otherwise you can't tell that it is fluorescent paint."

Fluorescent paint, hexagon socket head screws, Prado tires, scratches, wrenches, unknown male DNA, Shen Guanlin, Xu Zhanshan, Ma Xiangong, Shen Weijie, these known conditions constantly popped up on the large transparent screen in front of Zhou Ning.

Zhou Ning had a headache. Although he knew an unknown DNA, it would not be possible to compare all the men related to the deceased. This is unrealistic.

Xu Dayuan walked in, without Zhou Ning saying it, Da Zhao had already explained the discovery just now, Zhou Ning looked at Xu Dayuan.

"Xu Da, I think we still have to find clues from Shen Guanlin. Although Shen Guanlin has time to witness on the 21st, we still have to go through the monitoring."

Xu Dayuan took out his mobile phone, found a video and clicked on it, which was in a fast-playing state.

"The surveillance has been downloaded. He Chunyang and the others have analyzed it carefully. Shen Guanlin did have an operation during the day on the 21st. When he got off work at 06:30, he went out for 38 minutes, and then he received a call and came back with a box lunch.

We also verified this. It was the head nurse in the operating room who informed him that there was an emergency operation. The final time of the operation was 23:10, and the time to arrive at their community was 23:32. He said he was walking home.

The two unmonitored times are 22 minutes and 38 minutes respectively. In such a short time, the fastest round trip from No.45 Hospital to Baimahe Reservoir takes [-] minutes, which I think is unrealistic. "

Zhou Ning narrowed his eyes, thinking that they had studied this timeline many times, this time was indeed not enough to kill and throw away the corpse, but thinking of Shen Guanlin's son, Zhou Ning pulled off his mask.

"Did you check Sun Ailing's car Xu Da?"

"I asked someone sideways. It was a car that Sun Ailing's father gave her as a dowry. Sun Ailing usually drives it, and Shen Weijie probably also drives it occasionally."

Big Zhao leaned over, shaking his head constantly in his mouth.

"For a rich man, the dowry car was actually given to nearly a million. What does his father do?"

Xu Dayuan flipped through the text messages on his mobile phone, and Zhou Ning took a closer look. It said Qindao Star Screen Outdoor Advertising Company, and his eyes lit up.

"Outdoor advertising company, Xu Da, go and check this car. We just found three fluorescent paint on the shoulder of the deceased. I think their company can also use hexagon socket screws?"

(End of this chapter)