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

Chapter 429 Just do me a favor
Song Tiejun's case has come to an end.

For subsequent case handling, the serious crime team was directly handed over to the Tianzhou Municipal Public Security Bureau.

Of course, no one knows whether Song Tiejun really only killed five people.

No one can say clearly whether Wangjiahe was the only place where Song Tiejun dumped his body.

After all, even for the five corpses that have been found, from the perspective of traces found, there are no direct traces of Song Tiejun on the corpses.

However, the domestic basis for conviction does not require actual evidence, and logical reasoning can still be adopted.

If the suspect cannot prove his innocence to a certain extent, it can only mean that you killed the person.

Of course, there is not no direct evidence, such as the blood stains on the walls of Song Tiejun's house, the saws and axes used to dismember the corpse, and the stove used to burn the head.

All these can really kill people.

However, with current criminal investigation technology, it is impossible to clearly determine who they are.

"Teacher Lu, thank you for your trouble in the case we had last time."

Wang Chuanmin, captain of the Tianzhou City Criminal Investigation Detachment, has not been idle these past two days. They have been solving another murder case.

This is why Wang Chuanmin reported the case to the provincial department as soon as possible after the case was reported. They were really overwhelmed.

Moreover, the case was so difficult that Wang Chuanmin was not completely sure of solving it, so reporting it to the provincial department was the only way.

Although the case has been solved now, judging from the process of solving the case, there was a certain amount of luck.

If Sun Jianguo and Zhang Erhe had not gone to the old street, or if they had gone to the old street, they would not have had mutton soup at Song Tiejun's house.

Or maybe he drank the mutton soup but didn't talk to Song Tiejun about the past.

Then, it is really possible for Song Tiejun to escape.

At that time, it would be extremely difficult to solve the case if no new clues emerged.

Lu Chuan has been to Tianzhou City several times and is familiar with Wang Chuanmin, the detachment leader here.

"Captain Wang, you're too polite. The last case was just a coincidence, so I didn't help much."

The Tianzhou City Skeleton Case was an important battle for Lu Chuan to make a name for himself.

It was precisely because of his involvement in the Tianzhou City Skeleton Case that Lu Chuan came into the sight of the provincial department.

Only then did he have the experience of participating in many major cases of the provincial government.

"Teacher Lu, you are finished with the case here. When are you going to go back?"

"I'll send a car to take you back."

"Tomorrow, there's nothing going on here with the crime team. I'm going back to Haizhou City tomorrow."

"There's no need for a car. I can get back very quickly by taking the EMU."

Haizhou City and Tianzhou City are not far apart, so it is convenient to take a plane instead of a train.

"Hey, how can that be done? If Lao Qin knew about it, he wouldn't blame me for not fulfilling my duty as a landlord."

"I have been busy with a murder case recently. Otherwise, I must treat Teacher Lu to a drink!"

Listen to the words, Lu Chuan is no longer the dumbfounded boy he was more than a year ago.

"Captain Wang, I don't know if there is anything I can do to help you with your current case. If you need help, please don't be polite. When I came, Captain Qin specifically explained that Tianzhou City Criminal Investigation Detachment and Haizhou City Criminal Investigation Detachment We are neighbors and we cooperate closely, so let me learn more from you.”

"Ha ha!"

Wang Chuanmin laughed, who could not like someone like Lu Chuan? .

Be capable, not arrogant, and speak well.

"Teacher Lu, with your words, I feel relieved. Not to mention, the current case is really difficult. If you have time, can you help me take a look?"

"It's no problem when the time comes, but Team Wang, you also know that I'm surveying now, and others may not be able to help."

"Moreover, Captain Wang, just call me Xiao Lu. Teacher Lu really doesn't dare to call me that." "Haha, okay, then I'm not polite. It is indeed a clue from the field survey and fingerprints."

There was no such courtesy when solving the case. Lu Chuan followed Wang Chuanmin directly to his office.

"This is the file, Xiao Lu, you take a look first."

The dossier is not thick, only six pages.

The case is not particularly complicated.

A week ago, the Tianzhou City Beijiao Police Station received a report that a murder occurred in the Beijiao Logistics Warehouse.

The security guard patrolling the logistics base discovered a body in an abandoned warehouse.

"The scene was clean and tidy. The murderer even used a broom to clean up his footprints. No traces were left behind."

"And the other party left the murder weapon in the body of the deceased. We extracted some clues from the handle of the murder weapon."

The photo in the file shows a sharp bone-picking knife with vague fingerprint-like marks on the handle.

"Xiao Lu, look at this trace...can you do some identification and analysis?"

Wang Chuanmin was actually a little embarrassed.

Fingerprint identification requires fingerprints.

But...even a novice would know what was on the handle of the knife, and it had nothing to do with fingerprints.

On the second day after the incident, Wang Chuanmin actually contacted the provincial department. The fingerprint expert there had already looked at it and the answer was only three words.

joke.

Lu Chuan frowned, this thing...

"Captain Wang, is it easy to see the murder weapon?"

This level of "fingerprints" can't even be seen by looking at photos alone.

"That's no problem. The murder weapon is in the evidence room. I'll send someone to get it now."

10 minute later.

The murder weapon was already in Lu Chuan's hands.

Lu Chuan looked at it carefully and made a judgment.

The blurred marks on the knife handle are indeed traces left by fingerprints, but they are not direct traces left by fingerprints.

The murderer was indeed very cautious. He not only cleaned his footprints when leaving the scene, but also disguised his fingerprints when committing the murder.

The murderer was obviously very confident in his disguise, so even though there were vague marks on the handle of the murder weapon, he did not continue to clean it.

"Team Wang, this identification and analysis... is a bit difficult."

"And the method used by the murderer... was not as simple as wearing gloves."

Oh?
Wang Chuanmin only has a general understanding of fingerprint identification and does not have an in-depth understanding of it.

Lu Chuan continued to explain: "When the vast majority of murderers commit crimes, they wear gloves in order not to leave fingerprints."

"The most effective way to prevent fingerprints from being left behind is to wear cotton gloves, but cotton gloves are thicker and don't have good friction. It's not easy for the murderer to control the strength of his hands when committing the crime."

"There are also some murderers who wear surgical rubber gloves, but these gloves are also very thin and may leave the murderer's fingerprints vaguely imprinted on the murder weapon."

"Of course, the murderer's fingerprints can also be extracted from the inside of these rubber gloves."

"There are many ways to make fingerprints disappear besides wearing gloves."

"For example, applying glue on fingerprints can cover up fingerprint information, or soaking fingerprints with high-concentration radon sodium oxide can also remove fingerprints. Soaking them in dilute nitric acid can peel the fingers, and fingerprints will disappear within a certain period of time."

"In addition to the above methods, burning with cigarette butts, rubbing fingerprints mechanically, etc. can all make fingerprints disappear in a short period of time."

(End of this chapter)