Diary of a Criminal Investigator

Around the conference table, the members of the major crime unit sat in a row, with relaxed expressions on their faces, chatting and laughing.

For detectives, sometimes solving a case can feel like heaven one moment and hell the next.

One second, everyone was rushing around like headless chickens, unable to find any leads or make sense of the case, feeling like solving it was a long way off.

But the next second, you might get a phone call telling you the suspect has been caught.

The Wang Family River body-dumping case gave everyone this kind of feeling.

Even before the large-scale suspect screening began, the major crime unit had already preliminarily identified a suspect based on behavioral characteristics, victim background and work characteristics, and other information. It was very likely that the suspect lived on Northern Avenue and had once lived on Nanshan Road.

Even so, there are more than 30,000 permanent residents living on Northern Avenue.

The floating population is about 40,000, adding up to seventy to eighty thousand people needing to be screened, and this task cannot be completed in just a day or two; even ten days or half a month might not be enough.

Moreover, everyone present knew that such a large-scale screening was unlikely to yield any particularly obvious results.

One reason is that such a large-scale screening is bound to alert the suspect, who might prepare for the screening and leave no traces.

Another reason is that after going through a lot of interviews and investigations with no results, the officers conducting the screening might unconsciously lower their vigilance.

In other words, from past experience, if no substantial progress is made at the outset through large-scale interviews and investigations, the longer it takes, the less likely progress becomes.

What no one expected was that less than half an hour after the screening began, good news came.

"I heard it was an old policeman from the People Road police station, who is about to retire, who caught them with an auxiliary police officer?"

By the time the major crime unit arrived at the scene, only the suspect was left because Zhang Erhe was injured and Sun Jianguo had taken him to the hospital.

So the people from the major crime unit did not see Zhang Erhe and Sun Jianguo; only the police chief of the People Road station, Chen Jiang, was present at the scene.

"I have some acquaintances in Tianzhou who just inquired a bit, and these two are quite interesting. The old policeman is named Sun Jianguo and he retires in over a month, and the auxiliary police officer is a child of his neighbor, named Zhang Erhe."

Song Mingguang explained the situation he had learned about.

"Both of them know the suspect, Song Tiejun. Zhang Erhe and Song Tiejun grew up together, and Sun Jianguo watched both of them grow up."

"During the screening, they initially didn’t notice anything unusual, but during the conversation, they suddenly remembered that Song Tiejun had lived on Nanshan Road when he married into his wife’s family, but after his father died eight years ago, he divorced and returned to Old Street."

"After Sun Jianguo noticed something suspicious, he didn’t rush to take action but thought of reporting it first, and then consider whether to arrest him. As it turned out, just as they were about to leave, Song Tiejun suddenly intended to kill them, attacking from behind with a cleaver."

"Zhang Erhe had practiced Sanda before, so he handled himself well. Even though he was slashed on the left shoulder, he didn’t immediately lose his ability to fight."

"Well, this auxiliary police officer at least deserves a second-class merit this time, and he will certainly be promoted."

"I heard that this auxiliary police officer had already applied for the promotion quota this year, but it hadn’t been confirmed yet. Now with this case, it’s undoubtedly certain, and he won’t even need to use up the quota."

Everyone from various city bureaus was very familiar with the process of auxiliary police promotion.

From whatever perspective, that wound for Zhang Erhe was worth it, although, on the other hand, if the cleaver had struck his neck and severed an artery, the result could have been very different.

Just like the case last year in Tianzhou City, where an auxiliary police officer jumped into the river to save someone, even though he couldn’t swim well, wasn’t wearing a police uniform, and knew he could drown, he still jumped in without hesitation.

Sometimes, deciding to stand up like a hero or hide like a coward happens in just a split second.

"Alright, let’s talk about the case first, everyone."

Although the interrogation had just now not gone very smoothly, as Song Mingguang mentioned, they’ve caught the suspect, and now it’s a matter of grinding through the rest.

Li Donglin sat at the head of the table, feeling relaxed.

"I think the suspect, Song Tiejun, may have had a language-induced stress reaction, where hearing ’ma mapi’ triggered his murderous urge."

"I agree with Old Wang’s assessment. Language-induced stress reactions are not uncommon, but how the suspect developed such a reaction, I wonder if we should investigate his ex-wife."

Li Donglin nodded, having just asked Wang Song to suspend the interrogation, intending to find out why the suspect, Song Tiejun, would have such a language stress reaction.

Generally speaking, language-induced stress reactions have to do with habit formation and are not formed overnight; only when people experience severe mental pressure or stimulation might certain specific languages become stress reaction triggers.

Like training a pet dog, the dog can’t possibly understand human language, but when its owner calls the dog’s name, like "Dahuang," the pet dog will respond, knowing its owner is calling it because the dog has developed a stress reaction to the pronunciation of "Dahuang."

Of course, the mechanism of human language stress reactions is more complex compared to that of pets.

It cannot be achieved simply with repetition or tempting with dog food.

"I think it must be like this. Song Tiejun’s ex-wife is originally from Sichuan Province, so she must have spoken Sichuanese. Since he married into her family, he likely suffered grievances there."

’Ma mapi’ is a Sichuan dialect curse, and perhaps Song Tiejun didn’t have a good life in his ex-wife’s home. For example, they cursed him, bullied him, and over time, this reaction formed."

"Old Song, you handle this investigation, and get results as soon as possible."

"Yes!"

While the major crime unit was meeting in the conference room, at Tianzhou City First People’s Hospital.

"How’s Erhe doing?"

Outside the operating room, Sun Jianguo chased after the doctor who had just finished the operation.

"It’s not a major issue. The cut was quite deep and hit bone, but it didn’t affect any vital areas. There was some blood loss, but as long as he takes care to prevent infection and recuperates, he’ll be fine."

"Will there be any aftereffects?"

"Don’t worry, it won’t affect his arm’s functionality."

Hearing the doctor’s reassuring answer, the heart that Sun Jianguo had been holding finally relaxed.