Diary of a Criminal Investigator

The development of criminal investigation technology cannot be described as fast, but it isn't slow either.

Take fingerprint identification analysis for example. Over a decade ago, detectives were still using magnifying monocles, comparing thousands upon thousands of fingerprint cards.

At that time, everyone involved in fingerprint identification was nearsighted.

But even now, the old equipment like magnifying monocles haven't been completely abandoned.

It's like the allure of a mature woman compared to a young maiden; everyone has their preferences.

Nowadays, even though fingerprint collection no longer relies on cards, many people still compare fingerprints on their computer screens using magnifying monocles.

In this conference room, there are two relatively older participants still using monocles.

Most others are using the built-in image processing software to enlarge, distort, and preprocess fingerprints before running them through the system for comparison.

Yet no matter the method, whether using a monocle or a mouse.

Someone like Lu Chuan using a keyboard... quite rare indeed.

"Lu Chuan, are you a... hacker?"

Gao Wenxiang prided himself on being well-versed and knowledgeable.

He had seen tears run down while using a monocle against a screen.

He had also seen people print out fingerprints and compare ridge lines one by one.

But what was Lu Chuan up to?

The images on Lu Chuan's computer screen were switching crazily, streams of data flowing like in The Matrix in a corner of the screen.

Has fingerprint identification reached this level now?

Lu Chuan was performing numerical transformations, parsing fingerprint images into two-dimensional numbers, and then enhancing them through mathematical transformations.

"This is just a transition, it'll be quick."

Lu Chuan didn't elaborate.

Before achieving advanced fingerprint identification analysis skills, even someone like him, trained in crime scene investigation, couldn't fully understand his own methods.

Let alone explain them to Gao Wenxiang, who had only a college diploma after transitioning from military service.

During their recent smoking break, Gao Wenxiang had shared in detail his experiences on the police force.

It's as if people of a certain age enjoy sharing the meandering tales of their lives.

Back in the crime scene office, both Yang Sen and Old Bai loved recounting their past glories.

Fortunately, Lu Chuan was a competent listener.

This was part of why Lu Chuan had good social connections — he could control his tongue and not speak excessively.

In this office, Lu Chuan held a distinct position as the only detective from the criminal investigation team.

Besides the two technical officers from the Technical Identification Center, others often needed favors from the team.

So even though Lu Chuan's keyboard clacking was a bit noisy, no one paid much attention.

In their own units, their chatting voices were much louder than this.

Soon, everyone's attention returned to their computer screens.

Only Gao Wenxiang would occasionally glance at Lu Chuan's screen, savoring the Matrix-like imagery.

Ding!

The crisp notification sound awakened the detectives engrossed in fingerprints.

It was Lu Chuan's first time participating in the city bureau's fingerprint battle, and he didn't quite understand the significance of the ding: "Brother Gao, what's happening?"

Gao Wenxiang clicked his tongue at the policeman who had just stood up to stretch: "Someone just successfully matched a fingerprint."

Gao Wenxiang pointed at the policeman in the third seat across, who had stood up to stretch: "That's Sun Hao from the Technical Identification Center. In terms of technology, he's just a bit below Supervisor Liu Guodong, but he got the first fingerprint this time."

Lu Chuan looked up; Sun Hao was similar in age to Liu Guodong, a middle-aged man with a slightly chubby build and a friendly smile.

"Congratulations, congratulations, still Supervisor Sun is the best."

"Indeed, and it hasn't even been an hour, right?"

Colleagues promptly offered applause and congratulations.

For the precincts and the criminal investigation teams below, technical challenges they couldn't handle were usually handed over to two places.

One was the crime scene investigation office of the criminal investigation team, and the other the Technical Identification Center of the city bureau.

On work volume, the Technical Identification Center received more work from below.

After all, the criminal investigation team had its own cases, while the Technical Identification Center specialized in technical support.

Sun Hao waved his hand, not looking particularly proud: "Just a small case, got ahead, everyone continue."

The ding sound was a fingerprint identification success notification set up specifically during the fingerprint battle in the conference room.

At the same time, a leaderboard would appear in the bottom right corner of everyone's computer screen.

"Just click this to see the details of the fingerprint Supervisor Sun matched."

Following Gao Wenxiang's guidance, Lu Chuan clicked the notification box on the right corner and sure enough, up popped a leaderboard.

Sun Hao's name ranked first, with a red "1" following it.

Everyone else, including Lu Chuan, had a black "0."

"That '1' is clickable; you can check the case of the matched fingerprint."

Lu Chuan clicked as instructed; it was a case of an electric bicycle theft.

Sun Hao wasn't wrong; it truly was a minor case.

"Brother Gao, typically in our fingerprint battles... how many fingerprints do people successfully match?"

"Three to five at most; most cases are from this year, occasionally from before, but not many—sometimes it can be two or three years without one."

"Homicides?"

"Homicides?"

Gao Wenxiang smiled: "Even the provincial department's fingerprint battles don't always match homicides, let alone our city bureau's..."

Gao Wenxiang's smile told Lu Chuan the answer.

Never in history had a homicide been matched.

Lu Chuan nodded and continued with the layer processing of the selected fingerprint.

Homicide fingerprint identification analysis is truly difficult.

Almost an hour had passed, and Lu Chuan still hadn't completed the fingerprint preprocessing.

Yet it was close, and Lu Chuan estimated another half an hour to finish.

Time passed, and everyone's work gradually improved.

The fingerprint battle emphasized a concentrated working atmosphere.

It's also an opportunity for all the detectives proficient in fingerprint identification in Haizhou City's public security bureau to exchange techniques and build camaraderie.

"Lu Chuan, shall we have a smoke break?"

After nearly two hours of sitting, Gao Wenxiang felt a bit of backache.

For aging men, it's inevitable—not backache, then a urinary split, always a bit of weakness.

Just then, Lu Chuan had also completed the fingerprint preprocessing.

Feature point marking and data calculation were also done.

The only thing left was to run the data through the system.

"Sure, let's have one."

Grabbing the soft Chunghwa from the table, Lu Chuan pressed the enter key.

The system began automatic comparison.

In the smoking area, besides Lu Chuan and Gao Wenxiang, there were four or five others.

After working for two hours, smokers' cravings were kicking in.

"Let's introduce everyone, Lu Chuan from the support team, Supervisor Liu's proud student."

Gao Wenxiang was evidently a veteran, knowing most of the participants of this battle.

The detectives showed the due respect to someone from the criminal investigation team.

They greeted him.

Two people also offered cigarettes.

Lu Chuan quickly unwrapped the soft Chunghwa: "Take this one, have this one."

The smokers took Lu Chuan's offered soft Chunghwa with some surprise but said nothing.

Just a thank you, then extinguishing their previous red plums, Honghe, and the highest price Ziyun.

Smoking is the best social way for men, a maxim taught to Lu Chuan by his father.

Indeed, within a cigarette's time, everyone became familiar.

"Lu, we have a case in the High-speed Rail New District's Criminal Investigation Team, with Team Leader Ren Qiang, can you find time to see if you can ask about it?"

The speaker was Sun Miao from the High-speed Rail New District's Criminal Investigation Team.

Lu Chuan nodded; he was familiar with Ren Qiang, so it was no problem to help ask about the situation.

"Are you familiar with Sun Jun, the team leader?"

Sun Jun... Lu Chuan nodded, not too bad.

"What about Wang Changjiang, the forensic doctor? I need a toxicological test, but there's a queue at the technical identification center..."

The connections and framework thus opened up.

After two cigarettes, Lu Chuan's pack of Chunghwa was half empty, and everyone returned to the conference room.

Then, everyone stood up, giving a salute to the incoming individuals.