"Xiao Lu, the handlebar is the key point. Whether the other person is pushing an electric bicycle or riding an electric bicycle, the handlebar is the part that the murderer must touch."
Yang Sen imitated the posture of driving an electric car and analyzed the places where the murderer might have touched.
"There are no people around the two kilometers around Xingfu Reservoir. It is unlikely that the other party is pushing an electric car..."
Liu Guodong picked up a strong flashlight and shined it on the pedals of the electric car, carefully observing whether there were any footprints in the room.
When pushing an electric scooter, the other person cannot touch the pedals, but when riding an electric scooter, you will inevitably leave footprints on the pedals.
Lao Bai was cleaning the hair in the rear wheel bearing: "The body should have been placed across the back seat, so that the hair would not get caught in the bearing."
"Ding!"
"Advanced mission: By surveying the electric vehicle, we collected fingerprint information to help the action team locate the suspect and solve the case of corpses buried in Xingfu Reservoir."
Lu Chuan, who accepted the task, paid attention to the position of the armrest of the back seat.
If the murderer wants to push the electric car into the reservoir, his fingers are likely to hit the armrest of the back seat.
While Lu Chuan and others were investigating the electric vehicles, the investigation criminal police of the action team were also rapidly advancing their work.
"Team Qin, the origin of the electric car has been found out."
Ren Qiang took the electric vehicle registration information given by the traffic police: "The owner's name is Wang Song, and he owns a small restaurant."
"It was stolen three days ago. The local police station has all the alarm records for Wang Song."
Three days ago, it was the time when the victim was killed.
"Where was the electric car stolen?"
"No. 28, Beihu Road, right in front of Wang Song Restaurant."
"Is there any surveillance video?"
Ren Qiang shook his head: "The car was parked in a blind corner of the surveillance area, and no trace of the car thief was found."
"Check, conduct a key investigation on this Wang Song," Qin Yong thought for a moment and began to arrange the next tasks.
Qin Yong has seen a lot of thefts committed by guards.
"Also contact the traffic police. The murderer who stole the electric car and dumped the body will definitely leave video data along the way."
"Determine all the traffic sections from Beihu No. 28 to Xingfu Reservoir, and call in all the monitoring. No one can be missed!"
What is the murder mechanism? It means trying your best, investing the most resources, and solving the case in the shortest time!
In the detachment courtyard.
Liu Guodong and others had gloomy eyes, looking helplessly at the electric car in front of them.
"Old Liu, the electric car has been soaked in water for too long, and there is no way to extract fingerprints."
In one afternoon, there was no progress in the current survey.
However, Lao Bai has already completed the DNA information comparison.
The hair in the rear wheel bearing of the electric vehicle belongs to the deceased.
At this moment, only Lu Chuan was squatting on the ground, scanning every part of the electric car inch by inch.
Liu Guodong thought of the corpse fingerprints extracted by Lu Chuan that morning, which were extremely complete.
There was also the matter of helping Operation Two Team Ren Qiang and the others extract fingerprints at the scene of an arson case in the southern suburbs a few days ago.
Coupled with Lu Chuan's careful and serious look now, he had expectations in his heart.
"Xiao Lu, is there anything you can do?"
Although Lu Chuan also frowned slightly at this moment, his expression was still relatively relaxed.
The intermediate fingerprint collection skills rewarded by the system include many techniques and methods.
Especially to deal with fingerprints caused by fire or blisters, there are special fingerprint collection methods.
Although the electric vehicle involved in the case had been soaked in water for three days, Lu Chuan was still able to collect residual fingerprint information.
"Master, I made some discoveries."
Lu Chuan took out a purple light from the discovery box and shined it on the handlebars, back seat and pedals of the electric vehicle.
"I have carefully observed these places and there are no traces of wiping."
Liu Guodong nodded: "There are indeed no traces of wiping. There should be fingerprints on it, but after being soaked in water, it cannot be extracted at all."
Liu Guodong has just tried it, and ordinary physical and chemical methods are unable to extract fingerprints.
After three days of soaking, the sweat that forms fingerprints has long since dissolved.
Even the water-insoluble part of the grease is so diluted that it cannot develop fingerprints after long-term soaking.
In the field of current survey, the most fearful thing is the water case.
The longer time passes, the less you can discover.
Lu Chuan nodded: "After soaking, conventional methods cannot extract fingerprints, but some special methods can still have some effect."
Turning off the purple light, Lu Chuan relaxed his brows and said, "There will be some problems in extracting the completeness of the fingerprints."
oh?
There is a problem with the integrity, but it cannot be extracted?
Liu Guodong raised his eyebrows: "Xiao Lu, do you mean it can still be extracted?"
"Yes, but I need to prepare."
after an hour.
Lu Chuan returned to the courtyard again.
This time, he had a small watering can in his hand.
For this hour, Liu Guodong and the other three had been following Lu Chuan.
Witness with your own eyes how Lu Chuan evolved from a criminal policeman to a... chef.
Yes, chef.
This guy has been hanging around the detachment kitchen for the past hour.
I went through the bottles and jars inside.
A bottle of dark stuff was prepared.
"Xiao Lu...can you...do it?"
Lao Bai was a little confused. Although he didn't understand the details of what Lu Chuan was doing, he knew that Lu Chuan was making his own fingerprint developer.
However, doesn’t this thing only happen to the legendary masters?
Lu Chuan...make your own fingerprint developer?
Liu Guodong's eyes narrowed slightly and he looked at the small watering can in Lu Chuan's hand: "Lu Chuan... are you sure?"
Fingerprint developer is available in the criminal investigation detachment and is distributed from above.
In fact, the ingredients are very simple, mainly water and some chemical coagulants.
This fingerprint developer is universally used across the country and has a stable structure. It is a commonly used material for fingerprint extraction.
But before uniform distribution, each place had its own commonly used fingerprint developer.
In history, there have been many cases where on-site fingerprints were damaged due to unstable developer.
Therefore, homemade fingerprint developers were no longer allowed to be used.
Lu Chuan's ability to make his own developer shows that Lu Chuan's ability in collecting fingerprints has surpassed that of Liu Guodong and the others.
But on the other hand, if there is a problem with the developer, it destroys the fingerprints on the electric car.
This responsibility belongs to Lu Chuan.
It is normal for an electric vehicle to be immersed in water for three days and fingerprints cannot be collected. No one can blame the people in the current survey office.
The worst case scenario is to report it to the provincial department and have experts from above come over to investigate.
However, if the developer destroys the fingerprints, the experts coming from above will not be able to collect the fingerprints.
Then this responsibility belongs to Lu Chuan.
This is also the reason why cutting-edge technology is rarely used in the field of criminal investigation.
Stability is the lifeline of the criminal investigation field.
Lu Chuan obviously understood the meaning of Liu Guodong's words.
He cares about himself.
As for concealing the use of developer, that's impossible.
Fingerprint developers are chemicals and will definitely leave traces after use.
These must be recorded. This is a matter of process and no one can violate it.
So, should Lu Chuan take the risk?
