Although the content of the case analysis meeting of the Criminal Investigation Detachment was serious, the style of the meeting was actually relatively relaxed.
All criminal police officers participating in the analysis meeting can put forward their own suggestions or guesses.
Of course, there must be a certain basis for making guesses.
The basis mentioned here is not necessarily evidence, as long as it is reasoning that conforms to general logic.
In homicide case analysis meetings, the medical examiner is often the first to speak.
But this time, because there was only one human skin, it was impossible for the forensic doctor to do an autopsy.
Of course there is no autopsy report.
There won’t be much content in the report.
What's more, Wang Changjiang hasn't come back from his vacation yet, and Shen Yan is the only one at the forensic doctor's side.
Looking at the little girl next to him, Liu Guodong coughed twice and cleared his throat: "Let me say a few words first."
All eyes were focused on Liu Guodong.
"At the current survey, a preliminary survey of the painting has been carried out, and some fingerprint information has been extracted from the frame. Lao Bai and Yang Sen are comparing it."
"There is also DNA information in human skin. We have extracted it, but the comparison was not successful in the system."
Qin Yong nodded.
Compared with fingerprint comparison or even footprint comparison, blind DNA information comparison has an extremely low probability of success.
Unless there is a target person.
Just like the paternity test done by Lu Chuan and others.
Otherwise, with the current amount of information on less than 5,000 people in the Haizhou City Criminal Investigation Detachment’s DNA information database, if you want to make a successful comparison, you really have to burn incense and worship Buddha.
In any murder case, determining the identity of the deceased is the most important prerequisite.
Liu Guodong continued to report: "At this stage, we have completed the collection of fingerprint information on the oil paints, and Lu Chuan is now processing the skin."
"As for Xiao Shen, from a forensic perspective, what are the findings?"
This was Shen Yan's first time attending a case analysis meeting, and her nervous palms were already sweating: "The skin has been soaked in formalin, so it is difficult to determine the time of death of the deceased more accurately."
"But judging from the fact that DNA information can still be extracted, the time of death should not exceed a month."
This is the estimated range of death time that Shen Yan called Wang Changjiang to confirm.
Because skin soaked in formalin will lose activity within a month at most, making it difficult to extract DNA information.
The skin cells are essentially completely saturated with preservatives.
Ordinary extraction methods simply cannot work.
Of course, this does not mean that there is no way to extract DNA information, but it requires some special processing.
There is really not much effective information that can be obtained from a piece of human skin.
Qin Yong turned his attention to Sun Jun and Ren Qiang.
"The painter whose name is marked on the oil painting is Liang Song. He is a local grassroots painter in Haizhou City. Preliminary inquiries have been made."
Sun Jun began to report Liang Song's inquiry.
"He did not admit that he painted the painting. Judging from the questioning process, he should not have lied."
Ren Qiang's second action team is responsible for investigating and questioning the staff in the exhibition hall: "I don't get much effective information here."
"The exhibition hall was set up on Thursday, and this painting was transported directly from Liang Song's studio by porters."
"My people are checking the video surveillance of that day, and there is currently no possibility that the oil painting was transferred."
"As for being subcontracted in the exhibition hall..."
Ren Qiang expressed some of his guesses: "The possibility is relatively small. There is surveillance in the exhibition hall. Although there is no direct surveillance on the painting involved, it is very difficult to transfer an oil painting of nearly one square meter."
The painting is certainly not small if it can hold a piece of human skin.
"What do other people think?"
Qin Yong looked around again. Everyone knew that at this time, as long as everyone had reasonable speculations, they could speak freely.
Zhang Hui looked around and spoke first: "I think the focus of the investigation should be on this grassroots painter Liang Cong."
"He said he had never painted this painting, so how could he explain that the painting appeared in his studio?"
"Also, when the porter at the exhibition hall went to transport the oil painting on Thursday, he didn't even take a look?"
"You just gave a painting that you didn't draw to the porter?"
"There must be something wrong with this Liang Song. These things cannot be justified at all."
Zhang Hui's speculation has been recognized by many people.
Qin Yong looked at Sun Jun.
He was the one who interrogated Liang Song. Since he just said that Liang Song did not lie, these questions should have logical explanations.
Sun Jun nodded: "Let me talk about Liang Song's situation."
"First, when the art exhibition invited him to participate in the exhibition, it sent him a formal invitation letter."
"And Liang Song also responded to the invitation letter and made it clear that the painting he wanted to exhibit was called Dry Well Beside the Wheat Field."
“This has been verified by the reply letter we received from the exhibition hall.”
"What about the time? When did he reply?"
"Early August, August 2nd to be exact."
Sun Jun's group has obviously done a lot of work. On the conference room screen, a photo of the reply letter was displayed: "Liang Song confirmed his participation in the exhibition two months ago, and the forensic conclusion just now is that people The owner of the skin had been dead for no more than a month.”
"Second, in Liang Song's studio, in addition to his paintings, there are also paintings by his students."
"I have sent people to see the scene. His studio was renovated in a warehouse in the southern suburbs. It is very large and contains more than two hundred oil paintings."
"Among them, only fifty-six were actually painted by Liang Song."
"Third, Liang Song was not present when the studio moved out the paintings involved in the case last Thursday. He was collecting scenery in the suburbs at the time. Two students can testify."
"Fourth, when the porters moved the painting, the painting had already been packed. Lao Ren and I touched it. The porters at that time did not check the name of the painting, and they had no obligation to check it."
"They just went to move it. As for whether what they gave was the girl in the wheat waves or the dry well next to the wheat field, they didn't know at all."
"Where's the surveillance?"
Qin Yong frowned: "Is there surveillance in the studio? Can you find out who made the packaging?"
Sun Jun shook his head: "There is no monitoring. We are now investigating Liang Song's students."
When Liu Guodong's people were holding a case analysis meeting, Lu Chuan's work also entered the most difficult stage.
Fingerprint collection on skin.
Different from the fingerprint collection on paper that Lu Chuan had done before, and different from the fingerprint collection on the picture frame just now, the fingerprint extraction on the skin uses reverse thinking.
Since the skin itself has sweat glands and sebaceous glands, it is very difficult to collect fingerprints on living skin.
Because the material on the surface of the living body's skin will assimilate the fingerprints covering it.
Deactivated skin, which is what Lu Chuan is encountering now, will be simpler in comparison.
When the murderer soaks the skin with formalin, as the preservative penetrates the cells, it will also fix the fingerprint chemicals left on the skin by the murderer.
Of course, if the other party was wearing gloves at the time, that would be a different matter.
Lu Chuan has already started to take action.
