There are many types of bloodstains at crime scenes!

There are pools of blood formed by massive blood loss, dripping blood formed by vertically falling blood, flowing blood columns formed by flowing down the surface of objects, and so on.

These bloodstains each have their own function.

Like dripping blood.

The overall shape is relatively round, and there may be small blood spatters around it, which can be used to determine the location of the victim or murderer at a certain moment, the height of the blood dripping, etc.

In this case, what is particularly critical is the splattering, falling and throwing of blood.

Blood splatter usually refers to the blood stains formed on the receiving object when blood vessels in the human body rupture and blood droplets are ejected due to blood pressure.

Blood splatter refers to the situation where a weapon hits a person or an object, and at least one of the two is covered in blood. Due to the force of the impact, blood droplets splatter, forming bloodstains.

Throwing bloodstains refer to the blood on the surface of the murder weapon. When the murderer swings the murder weapon, blood drops fly out due to centrifugal force, forming bloodstains.

therefore!

In this case, the lasers emitted by the splattered blood and the falling blood on the wall formed a convergence area where Matsumoto Kozo's body was hit by the hammer.

The laser convergence area and shape corresponding to the thrown bloodstain are very different from the previous two.

The overall shape is curved!

The corresponding trajectory is naturally the murderer's hammer swing.

Moreover, the direction of the weapon's swing can be determined by the characteristics of the two ends of the bloodstains, and it can also be inferred whether the bloodstains were formed when the murderer retracted the hammer after the attack, or was swinging the hammer to attack.

By combining the splattered blood, sprayed blood and thrown blood, as well as the murderer's arm span, the length of the murder weapon, the victim's height and body shape, etc., it is basically possible to analyze the entire process of the homicide from beginning to end.

During this period, details such as the murderer's attack process and the victim's resistance and escape can all be found.

While fine-tuning the angle of the laser emitter, Shen Ting measured various data in the laser convergence area to reconstruct the course of the case.

The data he collected made him certain that the person who hit Matsumoto Koqing was neither Zhang Li nor Yu Qingwei.

The size of the murderer "indicated" by the bloodstains is very different from the other two.

at the same time!

The surrounding police officers looked at Shen Ting's actions curiously, their expressions becoming more and more shocked.

Everyone actually paid enough attention to Shen Ting's ability to analyze bloodstain patterns, but the police officers were still shocked when they saw several laser convergence areas.

The area where the lasers splashed and splattered blood converged appeared as a square with a distinctly curved edge.

Of course, not the entire square, but one or two sides of the square.

Because only the blood in the direction of the hammer can splash onto the wall, the error is relatively small;

On the other side of the hammer, after the splattered and splashed blood flew up, there was no support, and most of it would drip to the floor due to gravity, resulting in a relatively large error.

What surprised the police officers was!

The arc-shaped edge where the lasers converge is almost exactly the same size as the murder weapon deduced by the forensic doctor.

"Isn't it said that the string-pulling method has a larger error?"

"I think Team Leader Shen's accuracy is much higher than the software."

"Yeah, even the outline of the murder weapon can be shown. That's amazing!"

"And the tossing bloodstains and the corresponding laser arcs are so vivid.

I felt like I saw the entire movement of the murderer swinging the hammer and attacking Matsumoto Koqing."

…

As the police officers marveled at this, Shen Ting became more and more surprised.

He had a basic understanding of the entire murder process, and there was nothing particularly special about it.

First, the murderer held a hammer and hit Matsumoto Koqing's body several times against the wall in the living room.

The first hit should have hit Matsumoto Koqing's head, and he fell directly to the ground!

Afterwards, Matsumoto Koqing raised his arm to block, and according to the autopsy, his forearm bone was broken.

Matsumoto Kozo crawled backwards towards the wall behind him to avoid the attack, and his sternum and ribs were broken during the process.

Finally, Matsumoto Koqing climbed to the corner between the two walls, where he lost his strength and collapsed.

The murderer continued to attack the head several times before stopping.

Judging from the bloodstains, there were three people at the scene during the entire process——

In addition to the murderer and Matsumoto Koqing, there is another person.

Therefore, with each attack, a portion of the bloodstains was missing, probably due to the obstruction caused by the body of a third party.

In addition to the murder process, the other conclusions analyzed by Shen Ting are interesting.

He first found the trace examination and marked a few places on the fluorescent photo of the bloodstain:

"The bloodstains here, here, and here probably don't belong to Matsumoto Koqing. Take a blood sample and go back to test the DNA."

"No problem, I'll be right there!"

While the trace inspection was in progress, Zhuo Yan came over curiously:

“Team Leader Shen, is the bloodstain morphology analysis finished?

What is the conclusion?

Can we confirm that Zhang Li and Yu Qingwei are the murderers?

Can you confirm their crime process? "

Shen Ting shook his head directly:

"On the contrary, based on the conclusions of the bloodstain analysis, I can confirm that—

Zhang Li and Yu Qingwei are not the murderers!

However, the one who hit Matsumoto Koqing with the hammer was someone I know..."

As Shen Ting was speaking, just when the police officers on the scene were most curious, he suddenly changed the subject:

"What about Zhang Li's daughter, Zhang Qianqian?"