"I also want to look at the evidence again. Let's review the papers first."
Jiang Yuan did not start the lecture directly because of the public's attention. The backlog of cases eleven years ago was a real backlog, and the grading work alone was quite arduous.
Now, since there is already a formal backlog task force and a team of 20 or 30 people, instead of just a few people silently tinkering, Jiang Yuan also wants to be more formal.
The first step in reopening the backlog is to sort out and sort out the clues.
Clues from the past must be taken out. If there is evidence that can be used for non-destructive inspection, it must be re-examined to see if the latest technological innovations can play a role. The evidence from the past must also be looked at to see if there are any errors, omissions or imperfections.
Someone also needs to read the information that the police have previously searched for. Someone needs to read the transcripts of the interviews, which can often be hundreds or even thousands of pages. If they can find clues or some evidence to support them, that would be even better.
"The case will not be withdrawn until the murder is solved" is still a gimmick to a large extent. However, it is indeed very necessary and even smart to leave one or two policemen on the task force to know the whole process.
On the "Backlog of Cases Task Force" side, the two policemen from the task force contacted, the older one has retired, and the younger one... is still an ordinary policeman from the Criminal Police Detachment. They can be brought to the scene to keep up with the progress.
When everyone was busy, Liu Jinghui sat next to Jiang Yuan and whispered: "You feel it too, right?"
"Feel...what?" Jiang Yuan looked confused.
"This case is different from others." Liu Jinghui looked solemn.
Jiang Yuan's expression suddenly became solemn: "You mean, it's possible..."
Jiang Yuan pointed upward with his hand, his eyes full of questions.
Liu Jinghui was stunned, stretched out his hand and took out another finger from Jiang Yuan, and said: "What I mean is that these may be a pair of male and female robbers. Well, it is not accurate to say that the robbers are male and female. It means that the suspects should be a male and female pair.
.”
"Hey, why?"
"Because there was no rape." Liu Jinghui's voice was low.
Seeing that Jiang Yuan was still puzzled, Liu Jinghui coughed twice and said: "This... I have done several taxi robbery and murder cases, and I have also studied some cases inside and outside the province. Let's put it this way, if taxis
The driver was a female driver, and she drove into the wilderness. If there was robbery or murder in the end, most of them would involve rape."
"The majority is not all."
"For those that did not involve rape, either the female driver was too old, or there were women in the gang. The rest, many of them would turn into robbery, rape and murder." Liu Jinghui sighed: "So, this case
There were obvious omissions during the investigation of the current case."
This is why Liu Jinghui gave this case a high score.
Jiang Yuan listened quietly to the explanation.
"I looked at the photo in the file. There was a long hair in the back seat of the car, but I looked for the evidence bag and didn't take any samples at the beginning. I guess the criminal police investigating the scene thought it was the victim's hair and looked at it.
It does look like it, but I think it’s more likely to be the murderer’s hair.”
Liu Jinghui said as he found the photo from the file.
There is a blood stain in the gap of the brown seat. The photographer wanted to take a picture of the blood stain, but a long hair can be vaguely seen next to it.
Jiang Yuan immediately took the victim's photo for comparison. After repeated judgments, he nodded slowly: "It's possible that the hair is somewhat similar to the victim's. The length and color are similar, but the curl is slightly different. The condition of the photo is too poor.
, we can’t be sure. However, even if it is not the victim’s hair, it may be left by previous guests.”
Regarding the taxi case, the annoying thing is that the vehicle seems to be a treasure trove of evidence. When you open it, you will find that the ownership of each treasure is in question.
In the process of extracting evidence, how to extract evidence and what evidence to extract is itself a test of current investigation.
First of all, it must be clear that it is impossible to extract an unlimited amount of evidence during current surveys.
An evidence bag costs a few yuan, which is nothing, but DNA reagents are not cheap. Domestic products cost a hundred or ten yuan at the current price. Moreover, there are always some imported products that are easier to use than domestic products. You want a higher price.
Accuracy, better sensitivity, always comes at a price.
It is normal to extract DNA traces from more than a dozen places at a murder scene, and it is also normal to extract hundreds of DNA traces. However, in such a large scene, it is actually impossible to extract everything from hundreds of places.
And this is not only a problem of expensive consumables, the workload of the laboratory is also limited. A DNA laboratory of a municipal bureau processes DNA test materials all day long, and the feedback time for ordinary cases is only on "weekends" and "afternoon"
Week" and so on.
Although murder cases are taken seriously, they cannot occupy unlimited resources.
Investigators, other technicians, or other criminal police officers always have to make some judgments and choices based on their own experience.
Obviously, judging from the circumstances of the case, the police officers who participated in the investigation of the scene at the time may not have thought that a woman would be involved in such a violent robbery and murder case of beheading. Therefore, when collecting the examination materials, they did not specifically examine the case.
Take out this hair.
Liu Jinghui said noncommittally: "I guess it's a man and a woman. Another reason is that there is only one bloody footprint at the scene, and the DNA extracted from the victim's fingernails has not been matched for many years. This kind of stability,
It’s also very rare. I bet they are a pair of desperate couples.”
"Do you think the killer would have committed another crime?"
"Most of the murderers who commit robberies and murders are repeat offenders." Liu Jinghui said: "There are only murderers who commit robbery once. When a good man goes to Liangshan, robbing homes and houses has become a daily business."
Jiang Yuan nodded and said: "This shows that the original purpose of the case is probably not robbery."
"Yes, the purpose should not be robbery, let alone murder." Liu Jinghui paused and continued: "Judging from the way of killing, beheading may seem cruel, but it is actually very unprofessional, and it also proves the murderer's amateurism.
Sex. However, there is something about the murderer’s methods. I think he must have been exposed to similar jobs, such as being a butcher or a doctor.”
"If it was a doctor, shouldn't he be killed and then divided?" Jiang Yuanxiao objected.
"It's possible." Liu Jinghui nodded and asked, "What evidence can you see here? Why did you give it a high score?"
"There was only one person's bloody footprints at the scene, a male, about 38 years old, 175 centimeters tall, with a slight lameness in his left leg." Jiang Yuan emphasized: "The degree of lameness is not too severe. It should be that the left leg is slightly shorter than the right leg.
But if you wear height-increasing shoes, you won’t be able to see it.”
Liu Jinghui's eyes lit up when he heard this: "No wonder you gave me a high score. This case should be ranked first. If you have a lame leg, it will be much easier to find someone."
A lame leg is very recognizable. If it is not concealed, people around you will basically notice it when you walk.
This is much easier to distinguish than two arms of different lengths, or two eggs of different sizes. It doesn't even require special attention.
"There is also DNA, but they didn't find it out back then." Jiang Yuandao: "I'm afraid the two of them are no longer in the area."
"Well... it's very possible. The investigation back then should have been quite detailed." Liu Jinghui felt a little heavy at this time. If the person left, or was a foreigner, the investigation would be ineffective.
Without investigation, the criminal police's combat effectiveness will drop by 30%.
"In addition, I agree that the murderer has butcher or related experience." Jiang Yuan said, "I think starting from this aspect, it is possible to find the person."
"The lame butcher? And there is DNA, which is indeed a breakthrough." Liu Jinghui nodded. After all, it is a murder case, and it is not easy to have so many clues.
But compared to the first case, there is no way to make a direct breakthrough in this case.
