National Forensic Doctor
Chapter 339 - 339 306

339: Chapter 306 339: Chapter 306 “I confirmed with the victim’s husband that their smart home system could control not only the lighting but also the heating lamps and exhaust fans in the bathrooms.

Besides, the air conditioning and the fresh air system are controllable too.

Even the shower head and the bathtub can be controlled, including the water supply and drainage…”

Captain Ma returned to the scene and couldn’t help but grouse as he reported, “Why would anyone connect all the appliances in their home to the internet?

Not only could it let someone else take control, but it also costs more money, right?”

“It should still be quite convenient though.

One-touch hot water, you could be sitting on the subway, and the bath at home could already be filling up.

By the time you get home, you can soak directly in the tub, isn’t that wonderful?” Tang Jia was the first to stand up in opposition, for this was exactly what she liked to do.

Captain Ma grimaced, “As for saving just a few minutes’ time…”

Wan Baoming hastened to say, “I’ve called the technicians over, when they arrive, let’s see if we can find the person who has used this software.

If the person just used it normally, they should have left some traces.”

Jiang Yuan listened to the others talk while he silently continued sweeping the bathroom.

No matter whether the murderer used this system or not, he had definitely committed the murder and staged the suicide scene, and it had to be done right here in this very bathroom.

Thus, the likelihood of leaving traces increased significantly.

Moreover, Jiang Yuan did not believe anyone could cover every base.

Someone who put a great deal of effort into fabricating the scene might not have enough time and energy to eliminate all traces.

Many people have great misconceptions in their thinking and approach to doing things.

For instance, consider how much effort and time it would take for a person to kill a Husky weighing over 100 pounds, hang it up, and then stage it to look like a suicide.

What about cleaning the bathroom?

Many people might never attempt to thoroughly clean a bathroom in their lifetime, and if you want to get every nook and cranny spotless without leaving a single trace, how much time and effort would that take?

If in the middle of the process, one loses strength and falls, breaking an elbow, they would have to start cleaning all over again.

Some stubborn players might just give up.

If they give up, then they can meet their fate at the execution ground.

These would still be murderers who get things done.

Some murderers have obvious shortcomings in daily life, making it even harder for them to kill without leaving traces.

For example, some people don’t know how to tie knots properly.

If they can’t get the noose right when hanging a body weighing over 100 pounds, they would sweat profusely while being careful not to stain the corpse’s clothes.

Then, with a pop, the rope comes undone, the body falls to the ground—what a nuisance, what a challenge!

Furthermore, if the murderer wants to stage the scene, a lot of methods can no longer be used.

Some cleaning agents can indeed destroy DNA, but they are not commonly used cleaning items, or the victim’s home might not have purchased them.

In that case, the murderer might simply have to risk leaving their own DNA behind.

This is the risk you face while trying to reap the benefits of staging a crime scene.

Jiang Yuan was now betting on the murderer not having cleaned the scene thoroughly.

His level 4 crime scene investigation skill could effortlessly identify problems in a crime scene that had been level 2 inspected.

An average murderer, if not professionally trained, why wouldn’t he leave any traces?

Of course, nowadays people who are knowledgeable may wear gloves, so fingerprints are unlikely.

Jiang Yuan did find plenty of skin flakes and hairs.

Especially inside the drain and the sink, where he retrieved short hairs and wiped off water stains.

The victim had long hair, as did her daughter, who was living in a school dormitory.

The victim’s husband, on the other hand, was nearly bald, and the hair he did have was quite long.

The source of the short hairs became a point of reflection.

Jiang Yuan carefully collected several strands of short hair and placed them in evidence bags, then examined a variety of toiletries.

Next, he wiped numerous suspicious areas with a box of cotton swabs, feeling somewhat relieved.

Compared to determining time of death, the acquisition of this kind of evidence seemed more concrete.

“That’s about it,” Jiang Yuan said as he collected items like towels directly into large evidence bags.

There’s no need to be frugal for the Criminal Police Brigade when it comes to cracking a murder case.

Killing someone is actually quite tiring, akin to slaying a Husky weighing 100 pounds and hanging it to simulate a suicide.

The bathroom environment is also enclosed, so sweating profusely is only natural.

If the murderer wiped his sweat, there could be DNA on the towel.

If the murderer let the sweat drip, then the water stains he wiped off many surfaces could contain his DNA.

If the murderer washed with water, then the sink that was wiped down could have his DNA.

The formidable aspect of DNA is that it’s detectable in very small amounts.

In an environment like a bathroom, unless you use cleaning and disinfecting agents appropriately, you could still leave DNA traces even after multiple water rinses.

The problem is that the murderer, in order to stage a suicide, can’t use unconventional cleaners, creating the possibility of leaving DNA behind.

The asymmetrical warfare between the killer and the police is just like this.

If the killer chooses to fake the crime scene, they cannot eradicate the evidence.

If the killer decides to eradicate evidence, then they must face the risk of oversights as well as the trouble and professional demands of carrying various cleaning items.

Similarly, they also face the risk of oversights.

Of course, they could also choose not to process the scene at all, opting for the shortest contact time and method.

However, when killers commit murder, it’s often an act of venting emotions, and those who cannot control their emotional outbursts are likely to lack the discipline needed during the crime.

On the other hand, the shortest contact method still must contend with street surveillance cameras, potential eyewitnesses, and the victim’s resistance.

Just like the case Jiang Yuan worked on previously, the 513 stabbing through the door case, that was already a case of lucky, brief contact, but once the thin layers of paper were punctured, quite a bit of evidence was still left behind.

However, had it not been for Jiang Yuan determining the time of death for the corpse, making the husband the prime suspect, the crime scene investigators probably wouldn’t have gone to such lengths to collect evidence.

Because the husband’s DNA would certainly be all over the bathroom, as for the presence of anyone else’s DNA, that is usually not investigated thoroughly.

Who doesn’t have a couple of people in their family leave some sweat beads in the bathroom?

The forensic technicians from the criminal police detachment continued their busy work in the living room and bedroom, hoping to collect something else of significance.

Homicides are different from other cases; they typically have a much stronger motive.

Without sufficient motive, someone without an antisocial personality wouldn’t kill so readily.

And in cases where the crime scene is staged, once the veil of fabrication is lifted, the truth usually becomes quite clear.

Just like initially, everyone was focusing on the victim’s husband.

If it wasn’t the husband who killed her, then the murderer must have had a strong relationship with her.

In the midst of the hustle, the technicians from the cyber security squad arrived as well.

Similar to the crime scene investigation boxes or the forensic doctor’s kits used by, the cyber technicians also have their own kit, which includes “brute force” data extraction tools commonly used for cell phones and naturally applied to other smart devices as well.

Jiang Yuan and others directly stepped out the door to wait.

The victim’s relatives and several neighbors were taken to the case handling center for statements.

The hallway suddenly became quiet.

At this moment, Wan Baoming looked around and said, “If it weren’t for the smart home technology, people like us would probably be hiding in things like the ventilation ducts by now.”

“Hiding around the corner, waiting for us to leave before jumping down?” Captain Ma cooperated quite well.

“Maybe the alarm was raised too quickly.”

“Right, the victim’s husband came home faster than usual this time.”

“Coming home quickly didn’t help, and, also, calling neighbors over without attempting to rescue the person first is quite unusual.”

A few of them muttered near the entrance.

Before long, the technician came out from inside, looked at their notes, and said:

“Indeed, someone at 10:21 AM turned on the bath heater, lights, and shower, and set the air conditioner to heating mode.

At 11:20 AM, they turned off the shower and controlled the bathtub to start draining.

At 11:25 AM, they turned on the exhaust fan, adjusted the fresh air system’s airflow, and switched the air conditioning to cooling mode.

At 11:35 AM, they turned off the bath heater, the exhaust fan, and the air conditioner.”

Captain Ma’s expression turned solemn, “Someone really did use this thing.”

Wan Baoming’s expression was also grave as he looked at the technician, “Can you find out who was controlling it?”

“We can only check back at the station, and if the person was cautious, we might not be able to trace them,” the technician replied.

Tang Jia then said in a quiet voice, “Can we see who previously connected to the Wi-Fi?

Like the records on the router?”

The technician replied, “We can see that.

What are we looking for?”

“Murders always have a reason, right?

If it’s not a property dispute, could this murder be due to a love problem?” Tang Jia gently suggested, “The killer seems to be very familiar with the victim’s home.

They must have visited before to know about these smart home technologies…”

“We can.

Let’s start with that approach,” Captain Ma immediately nodded and continued, “Find people and compare their DNA with what was found at the scene and see if there’s a match.”