1995, Starting as a Criminal Investigation Expert

There were nearly thirty people in the team, and the office was quite large.

Now it's filled with smoke and fire, like a heavenly palace.

Xu Qiang was also present, arms crossed, remaining silent.

Lin Wanping stubbed out his cigarette, grabbed his messy hair, and spread his hands, saying, "What do we do now? We don't have a single clue."

The crowd remained silent.

Han Jianjun and Zhao Yong on the other side remained silent.

The case was difficult to handle, and they were at a loss, powerless to do anything but to do their jobs well.

Xu Qiang tapped the table and said, "Alright, Wanping, since there's no match, it at least means that this person has no criminal record, or that he's a transient. That's a clue."

"If they are transients, then we should focus on checking hotels, rental properties, and taxis. They are unfamiliar with the area and need to have a place to stay and a means of transportation."

"If it was a joint effort between out-of-towners and locals, I don't believe there wasn't a word of it in the local area. Use your network and do some serious inquiries; you're bound to find out."

Xiao Rui, with his thick eyebrows and big eyes, nodded in agreement.

It would be best if the comparison was successful.

Even if they don't match, it can still explain something.

Xu Qiang added, "Today is the 30th, and the case occurred on the 25th, almost five days ago. This group has committed four crimes in less than ten days."

"After the death on the 25th, they'll probably be more cautious, but they might not necessarily flee. They might commit another crime. After all, they took such a big risk, killing someone, and only robbed a little over 20,000 yuan in total across four robberies. Won't they feel like they've lost out?"

"Could he be planning to pull off a couple more big heists before fleeing? So it's good news for us that Lao Han was able to complete the fingerprint comparison so quickly."

Then he turned to Han Jianjun and said, "That Li Shu is really good. Old Han, you should train him well."

At the original pace, it might take several more days to get the comparison results.

The efficiency has increased two or three times, and the comparison work was completed today, which has already played a significant role in the case investigation.

After all, it was not yet possible to determine whether the crime was committed by an outside gang.

When the topic of efficiency came up, Xiao Rui curiously inquired a few more questions about Li Shu's situation. Finally, he asked Han Jianjun if this new method would make fingerprint comparison faster in the future.

"That's right."

Han Jianjun nodded, agreeing that the new method could indeed greatly reduce the comparison time.

Xiao Rui said, "That's a good thing."

Fingerprint comparison remains an important investigative tool.

Then he said, "Then we'll use the old method, Lao Han. Send the fingerprints to other cities in the province, and use your connections to get them to help you match them as soon as possible."

If the local data doesn't match, the data from other places might.

Han Jianjun nodded, just about to complain that he didn't have that much influence.

This is no easy task; it requires a lot of manpower and resources to help with the comparison.

You're busy, and so are other people.

But then I thought, maybe sharing the comparison method would save face for me.

I'm really anxious because of this case piling up on my head.

After summarizing the findings of the visits and arranging tasks, everyone ended the meeting and went back to their respective work.

Back at the team, Han Jianjun handed the documents from the Tingyang Municipal Bureau to Zhao Yong.

Once the fingerprint comparison is complete, the task is finished for the technical team.

Continue doing what you were doing before.

It's not just this one case; there are many.

Then Zhao Yong was instructed to print out the suspect's fingerprints and fax them to other cities, requesting their assistance in the investigation.

The municipal bureau has a fax machine, but Han Jianjun doesn't know how to use it very well.

He himself prepared to make a phone call and ask for help.

If you don't ask for help, people really won't treat it as a big deal.

The first call was to Pingyu next door.

Han Jianjun was familiar with Wang Dezhong, the captain of the Municipal Bureau's Technical Brigade.

"Old Wang."

As soon as the call connected, Han Jianjun immediately got into character, greeting the caller in a very friendly manner.

Before they could exchange more than a few casual words, Wang Dezhong had already guessed Han Jianjun's purpose for coming. He immediately began to complain, saying that he was extremely busy with many cases on his hands.

Han Jianjun silently rolled his eyes, his tone becoming three degrees more friendly, and then mentioned that a talented person had joined his team and had come up with a brand-new fingerprint comparison method.

"I'm not lying to you. This case I'm handling would normally take at least five or six days to complete the comparison, but now, one day is equivalent to several days. The efficiency has increased several times."

Han Jianjun wasn't bragging, and continued, "Given our relationship, if I have this time-saving and labor-saving method, how could I not share it with you?"

Wang Dezhong on the other side was indeed surprised by this efficiency.

However, he didn't ask any further questions, and said with a smile, "Actually, it doesn't matter what method it is, Lao Han. I've figured it out recently. It still comes down to science and technology. Take the AFIS system that our bureau just implemented, for example. It's so efficient. You just input your fingerprint into it, and you get the results in minutes. The key is that it's accurate. Isn't that amazing?"

Han Jianjun's eyes widened suddenly: "You guys are on AFIS?"

Suddenly, I had this feeling of both fearing my brother was poor and fearing he was driving a Land Rover.

Wang Dezhong said, "That's right, it was just put on the list in May, 264 million. Mainly, our Director Sun said that if Ningshan has the manpower, Pingyu can't be sloppy either."

On the other end of the phone, Han Jianjun gritted his teeth.

What are you showing off for? 264 million, with round numbers, just to make yourself look good at math, huh?

Suppressing his frustration, Han Jianjun congratulated him and said, "Well, what a coincidence! Once you input your fingerprint, the results won't be out immediately, it won't take much trouble."

After showing off, Wang Dezhong said cheerfully, "Alright, given our relationship, how could I not help you? Just wait for my news."

After saying that, he hung up the phone.

Han Jianjun was so angry he wanted to smash the phone.

The AFIS system is fast. We faxed the suspect's fingerprints over, and the results came out in just over an hour.

Unfortunately, the match still didn't work.

What frustrated Han Jianjun even more was that Yanling next door also had an AFIS system.

However, they are still working on the fingerprint database, so it will take a few more days.

This made Han Jianjun feel completely resentful.

Renping Yu looked up to Ningshan, but what about Nanjiang?

Look at the license plate; Nanjiang is registered under the Ning B license plate.

Han Jianjun couldn't sit still any longer and got up, intending to have another chat with Director Tang.

Meanwhile, while other teams were busy with other cases, the trace evidence investigation team also had work to do.

Zhao Yong simply handed the fingerprints that Tingyang had sent over to Li Shu and Tan Guoxiong, the two newcomers, as a practice exercise.

Fearing that the two of them wouldn't be able to handle it, they asked Peng Rong to help them as well.

Anyway, now that we have a new method, it's more efficient, and three people are enough.

Li Shu was actually quite worried about the case in the High-tech Zone, but he knew that worrying about it was useless, so he could only focus on doing his current job well.

I checked the fingerprints.

There are three and a half, or even half, of the palm prints.

The condition is alright. Although it was extracted from a steel pipe, the suspect's hands may have been stained with oil, so it is still relatively clear.

Li Shu followed Peng Rong into the archives room, carrying out stacks of fingerprint cards.

At this moment, Li Shu thought of some methods within the system.

For example, the archive coding method we saw before.

The municipal bureau's fingerprint database will make a basic classification based on the year of collection, gender, whether the person is from out of town or local, and which district or county/city, and store them in different metal cabinets.

This is equivalent to a primary classification.

Then comes the secondary classification, which is which finger and the tattoo pattern.

That's the end; there's no further subdivision.

The method mentioned in the system, according to my understanding, is to some extent based on the encoding method of the AFIS system, which extracts a fingerprint feature point and encodes it in a quantified manner.

This means that the nine characteristics of fingerprints have been further classified.

The system also provides some data.

For example, the endpoint feature has a probability of appearing as high as 58%.

Following closely behind are the bifurcation points, which account for 38%.

The lowest probability is the crossover, with only 0.3%.

Each feature point may appear multiple times on a fingerprint.

Therefore, this encoding method performs encoding in two directions.

First, fingerprints with low probability of feature occurrence are selected, filtered out separately, and placed into a three-level database.

Then select the endpoints and bifurcations with the highest probability of occurrence; these two features cover almost 80-90% of fingerprints.

Make a distinction based on the number of times each of their characteristics appears.

For example, if a fingerprint has three endpoints, then it should be stored separately.

Once we get the suspect's fingerprints, we see there are three endpoints, so we directly compare them with the three-level database.

This can greatly reduce workload and improve efficiency.