1995, Starting as a Criminal Investigation Expert

Tian Yu casually pushed off with his heel, set up the motorcycle kickstand, and was in a good mood, even humming a Teresa Teng song.

When I turned around, I was so scared that I shuddered.

Guo Xiangyang, with a stern face, almost brought his face close to his own.

Tian Yu clutched his chest and said, "Old Guo, what are you doing? Why are you walking so quietly? You scared me!"

Guo Xiangyang snorted: "That's because someone has something to hide, so they can't hear the footsteps."

Tian Yu was taken aback and asked Guo Xiangyang what he meant.

Guo Xiangyang said, "Stop pretending. Did you take Li Shu and the others to Zhaqiao?"

This question stumped Tian Yu, who countered, "How did you know?"

Guo Xiangyang sighed and said, "Old Tian, ​​you can't do this. Qiao Suqing's case has been going on for years. The young lady herself has come to terms with it. Don't keep harping on it."

"You know perfectly well how bad those fingerprints were. You can't do this to Li Shu."

Tian Yu immediately exploded upon hearing this, glaring at him and saying, "What do you mean I'm still holding onto this? That's a case! It's been four years, the person is paralyzed there, and we still haven't been able to find the suspect. I feel guilty, I can't get over it."

"Also, what do you mean I tricked Li Shu? I did this to solve the case."

He straightened his back, feeling no remorse.

"Come on."

Guo Xiangyang snorted. He had heard this explanation countless times and was no longer bothered by it. He simply reminded him, "Old Tian, ​​you've been a criminal investigator for so many years, you know better than me. Are you trying to make Li Shu resentful by letting him take on this kind of case?"

Having said that, Guo Xiangyang said no more and turned to leave.

He knew that Tian Yu's reasons were legitimate; it was for the purpose of solving the case.

But not all cases are the same.

Cases like this are almost impossible to solve.

Newcomers like Li Shu, young and just starting out, are full of enthusiasm and can easily get caught up in cases and get stuck on minor details.

Once trapped, just like Tian Yu, they became obsessed, constantly dwelling on it for years.

Guo Xiangyang had seen many cases like this before, and he really didn't want Li Shu to end up like that.

That's why I waited specifically for Tian Yu to give him a reminder.

However, as he went upstairs, another scenario flashed through his mind.

That is, Li Shu matched the fingerprints and solved the case.

But the thought only flashed through my mind.

He knew all too well how poor the fingerprints were in Qiao Suqing's case, as he had personally investigated the crime scene.

Trying to compare them is as difficult as ascending to heaven.

On the other side, when Li Shu returned to the team, everyone had already left work one after another.

Tan Guoxiong deliberately stayed behind, waiting for Li Shu.

He told Li Shu in the morning that he wanted to buy pots and pans so he could cook for himself.

Li Shu found it troublesome.

Since I often work overtime, I can eat in the cafeteria. If I really cook for myself, I won't save much money.

But Li Shu knew Tan Guoxiong's situation, so all he could do was agree. They made a deal that he would cook, Tan Guoxiong would wash the dishes, and the cost of the food would be split equally.

"Li Shu, about Team Leader Tian's case, you should reject him in a couple of days," Peng Rong instructed before hurriedly leaving get off work.

Tan Guoxiong asked what case it was.

"It's an old case. Let's go to the archives," Li Shu called out.

Even if you're going to refuse, you should at least consider the situation first.

In the archives, the two followed the clues and actually found the comparison data sent by the Tingyang Branch.

It mainly consists of a bunch of photos.

It's been sitting for several years and has already turned a bit yellow.

"Blood fingerprints?"

Tan Guoxiong glanced at it, immediately frowned, and said, "This was sent for comparison?"

Given these conditions, is it necessary to send them for comparison?

Li Shu counted them; there were seven photos in total.

Some have faces, and some have clothes spread out.

The incident occurred on May 23, 1991. It was already hot at that time. Qiao Suqing was wearing a white, collared, lantern-sleeved short-sleeved shirt, which was probably made of polyester fabric.

This type of fabric is smooth, so fingerprints are less likely to show up.

But they are all scratched fingerprints, incomplete fingerprints.

Then there are shoulder bags and wallets.

This handbag is made of suede, and the fingerprints on it make it unusable.

The wallet, on the other hand, had much better fingerprints, but the suspect may have been in a hurry while searching it, leaving behind scratches that could no longer be called fingerprints.

The only clear evidence is a pair of overlapping thumbprints on the plastic clip inside the wallet where the photos are kept.

The difficulty of overlapping fingerprints is even greater than that of incomplete fingerprints.

Especially blood fingerprints, which can smudge and appear at first glance as two bloodstains overlapping each other.

"What kind of case is this?" Tan Guoxiong asked.

Li explained the situation, his eyebrows already furrowed.

No wonder it hasn't matched after four years; the conditions are just too poor.

Tan Guoxiong didn't pour cold water on things like Peng Rong did.

He also provided assistance in the 9.5 case, and his fighting spirit was high. He carefully examined the photos and asked Li Shu if there was any way to help.

Li Shu found a horseshoe-shaped mirror and carefully examined each photograph.

This is a photo that has already been enlarged using film negatives.

"It's hard to say, it's a bit difficult."

The seven photos were clearly selected from those that were of good quality.

Of these seven photos, apart from those with overlapping fingerprints, the rest are all incomplete and damaged.

It was still badly damaged. Li Shu thought that it was probably because there was too much blood on his finger, which was why the central area was a blurry mess.

Only the edge area of ​​the fingerprint is relatively clear because it is not subjected to much pressure.

But clarity is useless.

In the outer area of ​​the fingerprint, the lines gradually become sparser, straighter, and follow a single direction, with far fewer feature points than in the central area.

On the system side, there are dozens of methods for displaying fingerprints, depending on the specific fingerprint conditions.

Many of these are new methods developed in later generations.

For example, one of its technologies, DFO fingerprint imaging, is quite effective for old blood fingerprints compared to traditional methods such as tetramethylbenzidine.

But what is referred to as "old" here is at most a few months old.

This case happened four years ago.

Given the current conditions for preserving physical evidence, the amino acids involved in that reaction would probably have already degraded.

After some deliberation, Li Shu closed the file and prepared to take it back to his dormitory to study it carefully.

That night, Li Shu didn't sleep much. He lay in bed, carefully reading through the various methods for dealing with blood fingerprints in the system.

If the fingerprints on the physical evidence are processed better, then the subsequent comparison will be much more efficient.

Unfortunately, after searching all night, I didn't find much.

The key is that this is an old case, and the physical evidence has been stored for too long.

Li Shu couldn't help but feel regret.

The system introduces numerous methods for preserving physical evidence, allowing DNA and bloodstains to be extracted and re-examined even after many years.

Such methods are not available at the moment.

Because he hadn't slept much, Li Shu kept yawning on his way to work.

Tan Guoxiong guessed that Li Shu had been thinking about it all night and asked if he had come up with a solution.

"no."

Li Shu smiled bitterly.

When I arrived at the office, people were already arriving one after another.

Zhao Yong suddenly approached him: "Li Shu, did you borrow a file last night?"

You must sign to record when borrowing files.

Li Shu nodded and, without hiding anything, explained the situation.

Upon hearing Qiao Suqing, Tian Yu, and Zhao Yong's brows furrowed immediately, and he said, "This old Tian, ​​he's never going to stop."

At that moment, he interrupted Li Shu and said, "Li Shu, I know about that case. The fingerprints were too bad. Since you've seen the file, you should know that it's even more difficult than the 9.5 case."

"These fingerprints can't be matched, so don't waste your time on them. Focus on your lecture, and I'll talk to Lao Tian later."

He muttered another word, "What a mess."

Which branch office doesn't have a bunch of old cases? Just because Li Shu matched a fragmented fingerprint doesn't mean everyone should come to Li Shu to handle these old cases.

Li Shu hesitated for a moment, then said, "Brother Yong, I still want to give it a try."