Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

Chapter 209 The second survey
Murders in reality are different from those in TV dramas.

Murder scenes are often more bloody, so bloody that most people will vomit at a glance, and ordinary people may faint when they see a pool of blood.

Not only that, but unlike the TV dramas where the murderer is very cunning and plans three or even ten years before killing, in reality there are very few people who plan to kill, most of them are passionate murders.

It is reality to draw a knife and face each other when there is a disagreement.

Therefore, after the occurrence of many murders, most of the murderers can be identified immediately.

Then there will be arrests, or some suspects will turn themselves in.

The case of the water district is a typical case of passion murder.

The scene of the crime was in the house of the deceased, and the murderer and the murderer had a conflict.

"The husband and wife quarreled. In desperation, the husband took out a kitchen knife from the kitchen and chased and hacked in the living room until he reached the bedroom."

Wang Yishan, captain of the Criminal Investigation Brigade of the Water District, was briefing Liu Guodong and Lu Chuan on the incident.

"Has the physical evidence collected at the scene been sent away?"

Generally speaking, Liu Guodong doesn't like to take on the second survey job.

After all, no one knows how the last survey was done.

For example, whether the DNA collection materials are in place, how clear the fingerprints are, and the traces left by the criminal police themselves for the first time, etc.

However, the criminal investigation brigade of the water district asked the detachment for help, and it was difficult to shirk it. The current survey here was also a colleague Liu Guodong had known for a long time, so he brought Lu Chuan over to have a look.

"I sent it back overnight yesterday. Old Xu originally wanted to analyze the physical evidence overnight, but he didn't expect to have pancreatitis..."

Although Liu Guodong has never had pancreatitis, he knows that this disease is more painful, and if it is not treated in time, it will be life-threatening.

"In this way, since the murderer has been caught, Lao Xu also made the first survey on the scene. Let's go again to see if there is anything left. If there is nothing, the main task is to analyze the physical evidence collected by Lao Xu. superior."

Liu Guodong glanced around and discussed with Wang Yishan.

"Old Liu, you are an expert in this area. You and Mr. Lu are busy first, and I will go back to the team to watch the interrogation."

Wang Yishan and Liu Guodong have known each other for more than ten years, which is one of the reasons why Liu Guodong came to the Water District Criminal Investigation Brigade to help.

Otherwise, Liu Guodong can completely shirk and ask them to ask other criminal investigation brigades for help.

The criminal investigation detachment is a higher-level unit, which can still be rejected.

While the two were chatting, Lu Chuan had already started working.

The scene was not complicated, but the deceased lost a lot of blood in the bedroom after being chopped down by her husband, and the whole bed was soaked in blood.

Many items in the living room fell to the ground, and the scene was a bit messy.

The murderer voluntarily surrendered after the murder, and the preliminary interrogation results were sorted out last night.

Wang Yishan just briefly described the process of the murderer committing the crime.

As for the reason, it is very simple, that is, the conflict between husband and wife, because of trivial matters more than ten or twenty years ago.

"Check the physical evidence and withdraw it if there is no major problem."

Liu Guodong has obtained the list of physical evidence that Lao Xu compiled last night.

Walk around the scene, and if you find nothing special, you can go back and do physical evidence analysis.

In fact, there is nothing too troublesome, the main thing is to detect the murder weapon.

For example, fingerprints, bloodstains, and the matching degree between the murder weapon and the wound of the deceased, etc. After confirming that there is no problem, the evidence can be locked.

Lu Chuan took the list and checked each item from entering the door.

Old Xu, who is in the water area, is still a professional. Lu Chuan has met him twice. He is in his 40s. He used to work as a front-line criminal policeman.

Without systematic training, but has its own set of methods.

And judging from the serial numbers on the site, Lao Xu's survey was very detailed.

Starting from the door, step by step to do it inside.

Now Lu Chuan is going to walk the road that Lao Xu walked over again to confirm that there is nothing missing, and the second survey will be considered complete.

In fact, most crime scenes will be inspected more than once.

This is especially true for some major cases, even homicide cases.

However, not everyone can enter the scene casually, even a single criminal policeman is not allowed.

Any criminal policeman, whether it is a criminal policeman handling a case or a technical criminal policeman on the spot, needs to go through approval procedures when entering the scene.

The scene of the fight should be more intense.

There were bloodstains on the walls, on the ground, and on the furniture.

From the door of the house, the bloodstains continued intermittently...

Ok?
Lu Chuan was taken aback suddenly.

Turning his head, he looked at the blood on the door frame of the entrance door.

The bloodstains were in a parabolic shape, spilling from the door to the inside.

Lu Chuan, who has mastered the analysis of intermediate-level bloodstain patterns, can even simulate in his mind the trajectory of the bloodstains, the angle at which the murderer wields the murder weapon, and even the general strength of the opponent's use.

Bloodstain analysis is the most common evidence found in most murder scenes.

In China, most murders are caused by cold weapons.

The common ones are kitchen knives, wooden sticks, axes, wine bottles and so on.

There are also unarmed killings, most of which are caused by suffocation.

And no matter which one, most of them will leave bloodstains at the scene of the crime.

Needless to say, killing people with knives, guns, sticks and axes, there must be blood.

Kill with bare hands, unless the person being killed has no ability to resist, such as being bound or stunned.

Otherwise, the person who was killed would definitely resist.

As the saying goes, rabbits bite people when they are in a hurry. No matter how weak the victim is, when his life is threatened, at least he can scratch the murderer's hand, right?

In some homicide cases, the murderer's epidermal tissue was extracted from the crevices of the victim's nails, which is the reason.

Of course, some murderers would put on gloves before strangling people, and even deliberately wear long-sleeved clothes to cover their arms. This is something that only experienced murderers or murderers who plan to kill can think of.

As for the current scene, it is an excellent case of bloodstain analysis.

Dripping bloodstains, columnar bloodstains, flinging bloodstains, splattering bloodstains, and pools of blood on the bed can be said to have everything that one expects to find.

Lu Chuan was puzzled by the blood stains at the junction of the wall and the door frame at the edge of the entrance door.

This is a throwing bloodstain. From the change in thickness of the parabola, it can be judged that the bloodstain swayed from the direction of the entrance door, and then adhered to the joint between the wall and the entrance door.

From the changes in the burrs on the edge of the bloodstain and the direction in which the bloodstain extends, we can get the positions where the murderer and the victim were standing and the direction in which they swung the knife.

In addition, on the ground in front of this bloodstain, there is an oval dripping bloodstain.

From the shape and size of the dripping bloodstain, the drop height of the source of the bloodstain can be measured.

The throwing bloodstains and dripping bloodstains, combined together, made Lu Chuan somewhat puzzled by the conclusions drawn.

And this doubt is, the scene dynamics shown by the bloodstains and what Wang Yishan said just now...

Different!
(End of this chapter)