Chapter 785

"If the killer is one person, then our previous investigation direction was completely wrong."

The annoyance in Lei Xin's heart flashed and vanished. He was also a veteran criminal investigator and knew that making mistakes was normal.

Most investigations are based on trial and error; who would dare say they can solve a case with 100% certainty? Niu Tong, a forensic expert in Qianjin District, also has a good level of skill, and his performance in past homicide cases can be considered commendable. Especially when it comes to the identification of various paper products, Niu Tong is even considered a master. Technical investigation personnel from many provinces and cities will even travel thousands of miles just to have Niu Tong personally perform a paper product inspection.

A single knife causing three types of wounds—only a forensic expert like Jiang Yuan would dare to look at the photos and provide such a conclusion.

Lei Xin quickly put the issue of accountability behind him, turned his head, and said, "In this way, the killer's motive for committing the crime is likely not for money."

"If a single person is carrying a machete, it is not convenient if it is for burglary." Liu Jinghui analyzed along with him: "If there were three people, it would be normal for one of them to carry a long-handled weapon. For a single person, there is no need to carry a machete weighing several jin. Even if he wanted to carry one, he should have brought one of better quality."

Liu Jinghui said in a slightly casual, conversational tone: "The weight of a machete is about the same as the weight of a bag carried by a woman. If it were a burglary for money, carrying such a machete would have a very low cost-benefit ratio."

"For self-defense?" Wang Chuanxing asked, mostly to play along.

Liu Jinghui followed the train of thought and said, "A small knife is enough for self-defense. Nowadays, if people see you holding a knife, most won't fight you to the death. Moreover, his knife is too poor; it rolled after a few hacks, and snapped after a few more. It clearly wasn't prepared for hacking people. It's more like he just bought a random knife outside."

"Random crime?" Lei Xin straightened his back, his brows furrowed tightly.

If this were a random crime, it would be like climbing from a muddy road to a ski slope; neither is an easy path to walk.

"At least it's not for burglary." Liu Jinghui's line of reasoning was very clear, and he turned to say: "If one expected to use such a machete for a burglary, the best way is actually not to go!"

This didn't need explanation, and Lei Xin nodded in agreement.

Burglary is for the purpose of theft, not for robbery.

The victim's family was not a wealthy or luxurious household; they were just an ordinary middle-class family. The total value of the property the killer took while rummaging through boxes and cabinets later was only a few tens of thousands of yuan. A family at this level could be found in any house in the same residential complex. Therefore, if the purpose was for money, and there was an expectation of the possibility of a fierce conflict, choosing a different house would be the most correct choice.

Or, one could do some preparation beforehand, break in when the family is away, or commit the burglary when only the hostess is home, which could greatly reduce the violent risk of the burglary. This killer clearly has attended the "school of society" and wouldn't be unaware of even such basic common sense.

Of course, there are some burglars who are the stubborn type, who just randomly pick a house to break into regardless of anything, stealing if they can, and robbing if they can't. But these people have generally been executed by firing squad. To say that we just happened to encounter one such person by pure coincidence...

"So, if the killer is a single person, and it's not for money, then it must be for the person?" Lei Xin followed Liu Jinghui's reasoning and asked again.

Liu Jinghui gave an "en" sound, and then said: "The possibility of it being for the person is relatively high."

"We can re-examine the surveillance footage. Previously, we mainly considered the situation of three people, although we also considered the situation of the three walking separately." Lei Xin gave a free comment, then with a *click*, flicked open his lighter to light cigarettes for everyone.

Jiang Yuan looked left and right, and seeing that no one else had any thoughts to share, he said: "The surveillance can be checked, but there's a bit less information. Does the technical investigation team have anything?"

"Not for the moment."

"The perpetrator is quite careful. No fingerprints or DNA were left behind. As for footprints, they wore shoe covers, and subsequent traces were basically destroyed. This family stockpiled a bit too much salt and cleaning agents." Jiang Yuan sighed.

"Active participants in the Double 11 sale." Lei Xin replied, and added: "We also considered situations like delivery drivers, but haven't found anything yet."

He checked a wave of delivery drivers because he remembered the case of Da Ma.

At this moment, Liu Jinghui *slapped* the case file shut and said: "It's not easy to investigate people. I suggest investigating the weapon. The quality of this knife is so poor that it doesn't look like it was bought in advance to commit the crime. Looking at the situation of this family, there shouldn't be a need to buy a large machete online either. Moreover, a thick-backed machete that has been sharpened is considered a controlled weapon anyway. I think the probability of an offline purchase is relatively high. It's very likely that the killer bought it from the surrounding area."

This speculation was slightly bold, but Lei Xin had no objections. For him, the more clues for the investigation, the better. If this clue leads nowhere, we can just investigate others.

Lei Xin had someone pull out the map and said: "If it's confirmed to be a machete, there certainly aren't many places where it can be bought. The hardware stores and renovation markets around here should all sell them. There are also wholesale markets that sell hotel supplies and camping equipment, as well as farmers' markets. Some vegetable markets sell them too, and there's also the livestock market and dog market over here..."

He said there weren't many, but when listed in detail, there were seven or eight types in total.

Lei Xin made phone calls to acquaintances at several nearby police stations, and in the end, listed more than 40 locations. The small ones were just a hardware store or renovation shop, and the large ones included building materials wholesale markets, with an area comparable to a university.

Lei Xin printed it out and said: "Alright, these are the places. Team Jiang, are you all going to rest, or..."

"I'll go to the livestock market and the dog market. I'll take the people from the cold case task force with me." Jiang Yuan was also willing to stroll around.

The livestock market and the dog market in Qinghe City are adjacent to each other. The livestock market is a fair for selling large animals, such as cattle, horses, sheep, pigs, etc. It also sells young animals and various related supporting products, such as ropes for tying cattle, soybean meal for feeding cattle, plows and harrows for cattle, and butcher knives for cattle. Nowadays, it has gradually declined, giving way to the dog market.

The dog market doesn't just sell dogs; it also sells various other small animals, but there are relatively few poultry. Nowadays, it is mainly focused on pets.

Jiang Yuan's cold case task force has over 20 people, which is enough to search a market, and perhaps even a bit overkill.

Lei Xin naturally had no objections and agreed immediately, then assigned the other addresses to other police officers of the criminal investigation team. The group of people then separately got into their own Jettas, Prados, and Audis.

Liu Jinghui followed Jiang Yuan into the A6 and smiled: "You don't usually go out on field duty. What made you think of it today?"

"The thick-backed machete was also my guess; what weapon the killer actually used isn't completely certain. Going to the scene to take a look will be more certain. Maybe we'll see some strange weapons." Jiang Yuan paused, then added: "This killer has a very strong anti-reconnaissance awareness. Using salt to pickle the corpse is quite an idea; we must pay a bit more attention to it."

"En, looking at this case, there are indeed many places that need attention." Liu Jinghui paused and said: "If the killer didn't commit the crime as an acquaintance, the motive is very problematic."

"How so?"

"Didn't Captain Lei ask in the conference room just now if it was a random crime? I didn't answer directly, but is it a random crime? It's actually possible. But if we try to understand it from the perspective of seeking money, this case cannot be explained regardless of whether it's random or not. But what if the purpose is the person? For example... breaking in to commit rape and murder?"

Jiang Yuan frowned.

"Judging from the photos of the victim's family, the mother and daughter were both relatively pretty. Of course, the daughter was still quite young, only 11 years old, but such perverts cannot be judged by common sense." Liu Jinghui said a few simple words, then added: "This is just my speculation. There were too many people just now, so I didn't say it first..."

"Actually, it makes sense." Jiang Yuan suddenly expressed support, which made Liu Jinghui stop involuntarily.

"How so?" Liu Jinghui asked.

"One reason I mentioned the thick-backed machete is that I saw suspected knife-back hacking marks on the heads of the two female victims. There are both knife-back hacking marks and rolled-edge hacking marks, but this can only be confirmed once the weapon is obtained. But in any case, when the killer hacked the two women, at least at the beginning, he might have had the idea of knocking them unconscious rather than killing them directly."

"If that's the case, then that's about it." Liu Jinghui sighed and said: "If it were purely to kill, he would have just killed them... In that case, we can also analyze the killer from the motive."