National Forensic Doctor
Chapter 689 - 632 Carbon Monoxide

Chapter 689: Chapter 632 Carbon Monoxide

Team Leader Zhou didn’t waste a moment, heading out to bring Tang Weili back to the police station.

If there were no direct suspects in contact, the police might consider surveillance. However, Tang Weili was the victim’s ex-boyfriend, which was a highly specific connection, immediately raising the degree of suspicion to 8 million. The fact that he hadn’t been outright convicted was a testament to a society governed by law.

On the other hand, although the case wasn’t a locked-room murder, it was certain that the murderer had meticulously planned the killing.

The method of murder was fundamentally different from victims being stabbed or hit on the back of the head with a blunt object.

While stabbings or clubbings could be explained as crimes of passion, of course, a court might not accept this; but during a police investigation, as long as you act within the limits of the law, there’s no need to think like the law.

As a natural person, one can imagine that even if you meet someone with a knife in your pocket, it doesn’t necessarily mean you intend to kill them. But if you’re carrying a bottle of carbon monoxide, the murderous intent is unmistakably increased.

You can’t get your hands on that stuff without a bit of effort.

And since the murderer had planned to this extent, for the police to resort to mere surveillance would only provide the murderer with opportunities to erase evidence.

Team Leader Zhou even prepared for the possibility that Tang Weili wouldn’t confess. After capturing him, he immediately took him to Tang Weili’s home with the crime scene team for a search. At the same time, they mobilized personnel to sweep through the garbage bins of the neighborhood where Tang Weili’s home was located.

All containers that seemed capable of holding carbon monoxide were searched.

Unfortunately, they found nothing.

But this time, including Team Leader Zhou and the others, everyone wasn’t in a hurry.

Facing a city of several millions, finding a murderer is truly difficult. It’s somewhat of an exaggeration to say it’s like finding a needle in a haystack, but it’s akin to the difficulty of catching wild yellow croaker in the vast ocean.

But if there’s already a prime suspect, the situation is much different.

Especially for a prime suspect in a major homicide case, the treatment they receive is virtually equal to a target of the United States Internal Revenue Service Criminal Investigation Division.

First, the detectives went through Tang Weili’s phone, then checked his bank account and the flow of funds. The third team traced his steps. Person, money, and belongings—all were clearly allocated for investigation.

People close to Tang Weili were also questioned and investigated one by one...

It might not be a tight dragnet, but the kind of net the police use is something many ordinary people might have never seen; things like checkpoints, recognition systems, barriers, and the like, were not available a few years back, yet now they’ve appeared out of the blue. Even the police need to learn and train for them—outsiders don’t know so much.

As for not using any electronic devices... As it turned out, Tang Weili did just that. He rode a bicycle from his own neighborhood directly to the neighborhood where the victim lived.

It’s still the theory of the wild yellow croaker—with the vast sea making it hard to find, but now they focused solely on tracing Tang Weili’s steps, and there was even facial recognition access control at the entrance of his neighborhood.

There really weren’t many people who left their homes at 5 o’clock in the morning.

Along the way, cameras were not always present, but whenever he went through checkpoints, his full face was captured.

As to why he left home at 5 in the morning, Tang Weili couldn’t provide a clear explanation, yet he was far from giving up resistance.

Standing before a one-way mirror like in the TV dramas, Jiang Yuan and the others looked at Tang Weili’s round face and round eyes, feeling the resilience akin to the bounciness of a Q-ball.

"Didn’t expect this little fat guy to have such a strong psyche," Mu Zhiyang remarked. "His own story is full of holes, yet he stubbornly claims he’s innocent. He’s quite stubborn indeed."

"He’s a businessman; he’s accustomed to being confronted and he can’t do much about it," Wang Chuanxing said, holding a pad full of documents.

Mu Zhiyang commented, "Why bother with this when you’re living a good life, running such a big hot pot restaurant? I can’t figure out what the murder motive is. If I had such a big hot pot restaurant, I’d get up at 5 o’clock every morning to cook hot pot."

"The hot pot restaurant’s business isn’t good; it’s losing money," Wang Chuanxing said while looking at the latest news. He flipped through the pages and added, "The turnover isn’t high, and with over thirty staff members, they spend more than one hundred thousand per month on salaries alone. Moreover, the lease is soon due. His financial situation seems pretty bad. Could this be a motive?"

Crime motives boil down to three types: greed, lust, and aggression. Financial situations are naturally one of the focal points of concern.

In the crowded little room, steaming with seven or eight people, everyone was slightly agitated and began discussing:

"Unless the victim, Yue Ling, sold her house, she couldn’t fill her ex-boyfriend’s bottomless pit. Moreover, how would Tang Weili benefit from killing her?"

"Did the hot pot restaurant open before or after the two broke up? Could there be any financial disputes?"

"The secret recipe of the hot pot restaurant?"

"The hot pot restaurant is about to go out of business; the secret recipe isn’t worth a dime."

"Could the two have been secretly in contact? The man’s hot pot restaurant is doing worse, and previous promises failed?"

Everyone speculated, each theory sounding somewhat reasonable, yet none supported by sufficient evidence.

Those with less composure were already pulling at their hair.

If there was an equal point of contention between the police and the criminals, the psychological battle would surely rank first.

When the suspects were in self-doubt and agony, the police were actually going through the same.

And from the perspective of a person in charge, observing the discussion among everyone also proved a classic truth: What’s the use of reasoning?

"How’s the search for the source of carbon monoxide going?" Jiang Yuan interrupted the discussions.

"No news yet," Wang Chuanxing checked and answered.

He had been thinking too, and from his own mode of thinking, finding evidence was the first thing he considered.

The most important evidence in this case was carbon monoxide.

Carbon monoxide could be produced by oneself, with car exhaust or incomplete combustion both being possible sources of production, so as far as scarcity was concerned, carbon monoxide was worth little. It was even present in the air itself.

But the victim’s death was acute. As is well known, deaths caused by carbon monoxide typically come in three types: lightning-fast, acute, and chronic, the latter often requiring half an hour of death time. A typical example, such as suicide by charcoal burning, is very slow, belonging to the slow production of carbon monoxide, slowly killing a person.

To achieve an acute death by carbon monoxide, the concentration has to be high enough—producing such a high concentration of carbon monoxide on one’s own is very difficult.

This must have been considered by the murderer; if it weren’t for high concentrations of carbon monoxide, the victim would realize something was wrong and simply open the door to leave.

If Tang Weili were the murderer, how did he obtain high-concentration carbon monoxide?

There were only two options: offline and online.

Offline, one could visit related shops, while online would mean checking sales records.

Online had apparently already been checked, while offline was being investigated by Team Leader Zhou.

Thinking back to the times he went to collect rent from the shops at home, where the poorly managed shopkeepers hustled and bustled, scrambling to find money to make payments, Jiang Yuan turned to Wang Chuanxing and said, "Tang Weili is a businessman; he might have more than one account under his control. Ask the staff at the hotpot restaurant, especially those in charge of finances, to find out about Tang Weili’s other accounts and see if there’s any record of purchasing carbon monoxide."

"We’ve already checked the accounts under Tang Weili’s name... You mean the account might not be in his own name? We’ve also checked a few accounts of other people from the shop," Wang Chuanxing said while looking through the records.

Jiang Yuan said, "Expand the search further, try our luck."

"Yes," Wang Chuanxing agreed and began making calls to arrange for personnel. Since Jiang Yuan had mentioned it was a matter of luck, they needed to expand their search broadly. The case was essentially already solved, so it was time to take some liberties.

Evening.

Jiang Yuan and his group went to eat mutton noodles in Changyang City.

Mutton soup is the essence of freshness. Whether mixed with noodles or mixed with rice noodles, as long as it doesn’t overpower the taste, it is delightful, and in the end, as long as the cook skims it frequently and the secret recipe isn’t too odd, the quality of the mutton will shine through.

Sitting in the mutton noodle shop, Yu Wenshu, who had found an excuse to return home late, cheerfully said, "Using the lingo of today, this shop is a ’hidden gem’ I’ve discovered. Sometimes when I go home at night, I stop by to eat a bowl of noodles before heading back."

Huang Qiangmin clicked his tongue appreciatively, "If it’s that delicious, I must try it."

"Mhm, you can pair it with some pancakes. Those with a smaller appetite can just eat the meat and drink the soup. Like someone who feels like they’re catching a cold, they come here, slurp down a bowl of soup, blow their nose a bunch, and the cold can get better by half," Yu Wenshu praised without reserve.

In fact, Yu Wenshu enjoyed anything as long as he didn’t go home.

Huang Qiangmin didn’t expose him, cooperatively sampled a pancake, and praised it a couple of times.

When it was time to leave, Yu Wenshu still seemed reluctant to part with the place...

Just then, a phone call came through to Yu Wenshu’s cell phone.

Yu Wenshu, just about to head home, glanced at the caller ID and immediately picked up. He didn’t say much before a sincere smile appeared on his face.

After hanging up, Yu Wenshu turned back and said, "We’ve found the source of the carbon monoxide. An online purchase record of carbon monoxide was found under the account of a veteran employee from the hotpot restaurant. The employee confessed that the account was registered with Tang Weili’s help, and Tang Weili usually had control over it!"

With that, Jiang Yuan and the others cheered up as well.

Yu Wenshu waved his hand, "I’ve got to go back and check this out. You guys rest first, especially Jiang Yuan—make sure to get plenty of sleep. Alright, I’m heading back to the station to see the details. You can come tomorrow to hear the results..."

Watching the excited Yu Wenshu return, Huang Qiangmin mused, "That’s our branch chief for you."

Liu Wenkai said thoughtfully, "Marriage makes a person grow... "