Zhou Ning laughed twice, such an abrupt action made the two of them scratch their heads.

"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 stone that is too suitable, so let's use this to simulate.

Hit with both hands horizontally, vertically with one hand, and vertically with both hands, so that the three movements are tested, and then compare the traces of the marble being broken, so that you can intuitively understand how the murderer injured the deceased. ”

Xu Dayuan nodded.

"It's okay to experiment, but what are you giving me marble?"

"I'm too high, it's not easy to hit when I lift it."

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

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

Zhou Ning glanced blankly.

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

Da Zhao didn't talk nonsense, wearing goggles, and raised the wrench horizontally with both hands.

"Boss, you're ready, I'm here!"

"Take aim, hit me and watch your head."

Da Zhao trembled and looked bitter.

"Don't scare me, boss, I'm here."

Saying that, Da Zhao picked up the wrench horizontally and smashed it towards the marble slab, the marble slab was smashed and splashed out of some debris, but it was not broken, Xu Dayuan also turned over the slate and looked at it, he could feel the strength of Da Zhao in his hand, and it was a little unexpected that it was not broken.

"It's not broken?"

Zhou Ning nodded, marked a 1 with a marker on the marble slab, and then motioned for a second piece, this time Xu Dayuan grabbed horizontally and raised his hands, and Da Zhao held a wrench in one hand and smashed it down.

With a snap, the marble slab exploded diagonally, and a lot of gravel was splashed like a force point, and the cracks were also presented diagonally along the force point, Xu Dayuan looked at it.

"This marble has cracks, the next time you smash it, avoid this brown-red pattern, smash the white here, and come back."

Zhou Ning hurriedly went to mark, and then got out of the way, Da Zhao held the wrench with both hands for the third time and smashed it down from top to bottom.

This time, the marble slab was not cracked, the wrench was inlaid on the marble slab, Zhao Xinli wasted some strength to shake it out, and the broken position was really the same shape as the wrench head, and a round C-shaped depression appeared, but this shattered was a little powerful, obviously the murderer was not as strong as Da Zhao.

"It seems that Xiao Zhou's forensic analysis is correct, the murderer smashed it vertically with a wrench when the deceased lowered his head."

"I don't understand, dressed like this, it's so cold outside, why can you make the deceased squat honestly, and smash the deceased's head without attracting her attention?"

Xu Dayuan was silent, Zhou Ning pursed his lips, looked at the wrench and then looked at the defect on the marble, and quickly rushed back to the autopsy table, restored the scalp of the deceased, and stared at the defect to observe.

"The murderer smashed the deceased with all his strength, but the strength is not as good as Da Zhao, but there is also a problem, just like Da Zhao's action just now, so that when he smashes the wrench, it will be set on the deceased's head, what will he do if he wants to pull out the wrench?"

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

"Hold on your shoulders or your head, shake it and pull it out."

Xu Dayuan nodded, he thought the same, but his eyes widened instantly.

"You mean clothes, there will be residues on the clothes of the deceased? I remember that the test report just said that the extract of the wound of the deceased was found on a male DNA that did not belong to the deceased? ”

Zhou Ning smiled, it seems that the subconscious movements of the people are almost the same, and he walked directly towards the evidence bag of the deceased's clothes, unfolded it, spread it on the stainless steel table, and said while looking for it.

"The unknown male DNA, I judged it to be bloodstains, the murderer had injuries on his hands, combined with the abrasions on the deceased's nose and eyebrow 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 when the deceased was about to get up, the murderer smashed the deceased's head from behind."

Zhou Ning said, looking at the deceased's nails, the deceased's nails were seen during the autopsy before, and they were cut very short, they were the kind of bald, and they couldn't wait to cut the flesh, because of her profession, Zhou Ning didn't think much about it at first, but looking at it now, maybe not for this reason.

Pull over the LED magnifying glass light, carefully observe the fingertips, the nail trim marks are very neat, not with nail clippers around the edge of the nail a few cuts, but directly cut bald.

Zhou Ning waved his hand at Da Zhao.

"Help me get the luminol spray and spray the deceased's nails!"

"After soaking in the water for so long, what blood stains can remain?"

Although he said this, he didn't stop, found the luminol spray, leaned over to Zhou Ning's side, and sprayed it carefully, on both sides of the edge of the deceased'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, so he reacted immediately when he saw this.

"The deceased scratched the murderer, and the murderer has excellent anti-reconnaissance ability, so even when throwing the corpse, do not forget to cut off the deceased's nails to eliminate all possible traces?"

Zhou Ning nodded.

"I think you can search the reservoir carefully, within 20 meters from the shore, maybe you can find the murder weapon, he won't take it away, and the murderer's home should be in the opposite direction to the White Horse River Reservoir, after all, we always say that it is far away and buried nearby."

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 deceased's clothes, observed inch by inch on the two shoulders on the back of the clothes, and when he searched for the right shoulder, there were three plastic things in the reverse, Zhou Ning fiddled with the front side for a long time, but he didn't see what kind of substance this was, and after touching it with gloves, it was still a little sticky, and it seemed to be a little reflective.

After soaking in water for so long, can it still be sticky, is it glue?

Da Zhao sighed, hurried over, thought for a while and said.

"It's fluorescent paint."

Zhou Ning looked at Da Zhao puzzled, he didn't understand these things, he didn't seem to have paid attention to where he used this thing, Da Zhao hurriedly said.

"On the highway on the headlights, there is a reflective strip on the middle of the separation belt, that is a kind of fluorescent paint, of course, some dance hall discotheques also do this, this thing dries faster than the general paint, but after soaking in water, it is estimated that there is no effect, this clothes are dry, otherwise I can't see that it is fluorescent paint."

Fluorescent paint, hexagon screws, Prado tires, scratches, wrenches, unknown male DNA, Shen Guanlin, Xu Zhanshan, Ma Xiangong, Xu Weijie, these known conditions kept popping up on the transparent screen in front of Zhou Ning's eyes.

Zhou Ning had a headache, although he knew an unknown DNA, he would not be able to pull all the men related to the deceased to do a comparison, which was unrealistic.

Xu Dayuan walked in, no need for Zhou Ning to say, Da Zhao had already said what he had just discovered, and 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 and found a video to open it, which was in a state of fast playback.

"The monitoring has been downloaded, He Chunyang and they have carefully analyzed it, Shen Guanlin did have surgery during the day on the 21st, and when he got off work at half past six, he went out for 38 minutes, and then received a call and ran back with a box lunch.

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

The two unmonitored times, 22 minutes and 38 minutes respectively, take 45 minutes to travel from the Eighth Courtyard to the White Horse River Reservoir in such a short time, which I don't think is realistic. ”

Zhou Ning squinted, thinking that they had studied this timeline many times, and this time was indeed not enough to kill people and throw corpses, but thinking of Shen Guanlin's son, Zhou Ning ripped off his mask.

"That Sun Ailing's car Xu Da, have you checked?"

"I asked someone on the side, it was a car that Sun Ailing's father gave her to marry, usually Sun Ailing drove it, and it is estimated that Shen Weijie also drove it occasionally."

Da Zhao leaned over and kept shaking his head in his mouth.

"A rich man, the dowry car was given nearly a million, what did his father do?"

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

"Outdoor advertising company, Xu Da went to check this car, we just found three layers of fluorescent paint on the shoulders of the deceased, I think their company can also use the hexagon screws, right?"