Coroner Coroner

"Hmm..." Maru Asai responded absently.

Immediately afterwards, after some contemplation, he couldn't help but ask Lin Xinyi:

"Mr. Lin Xinyi."

"Since the saliva spot can prove that Matsuo has been here."

"Then is there any scientific method... that can determine the exact time of saliva spots?"

Hearing this, Lin Xinyi was slightly taken aback.

He understood Asai Chengmi's intention in raising this question:

At present, the death time of the deceased is determined, and the crime scene of the murderer can also be proved.

So as long as it is proved that Matsuo appeared at the crime scene at the time of the crime, he can be more strongly identified as the murderer.

And as long as the exact remaining time of the saliva spots can be determined...

It can be further determined that at what time did Matsuo come to this utility room.

If this time coincided with the time of the incident, then the sum of these evidences would be enough to send him to court for trial.

"Determining the Exact Persistence Time of Saliva Spots..."

Lin Xinyi thought carefully along this line of thought, but in the end, he gave a disappointing answer:

"It's possible to—"

"Because the concentration of urea and amino acids in saliva plaques will change nonlinearly with the change of retention time."

"So as long as the concentration ratio of urea and amino acid in the saliva spots is measured and substituted into the regression equation, the remaining time of the saliva spots can be calculated."

"However, the remaining time of saliva spots determined by this method can only be as accurate as 'days'."

Hearing this, Asai also understood Hayashi Shinichi's meaning:

There is no way to solve this case just to be accurate to 'day'.

The remaining time of the saliva spots must be accurate to 'hour' to prove that Matsuo came to this utility room during the 10-minute break at 3 o'clock sharp.

"Is this idea really unworkable?"

"There is no way..."

"Can the residual time of saliva spots be accurate to 'hours', or even 'minutes'?"

Facing the dilemma set by the murderer, Asai Masato fell into deep thought.

And in this fog...

The unique perspective brought by his doctor profession suddenly made him see a direction:

"Takashi Matsuo... you have the flu, right?"

"Yes." Lin Xinyi was a little puzzled.

"What time is it?"

"10:50."

"Well... there is still hope."

There was a touching smile on the corner of Asai Chengmi's mouth, and the ponytail behind his head flicked excitedly:

"Extract the saliva spots first."

"Then hurry up and find ice cubes... No, dry ice, the TV station should have dry ice for stage effects!"

"Use dry ice to freeze the saliva spot sample!",

"Why use dry ice?" Lin Xinyi asked curiously.

He had never seen this trick before.

But Asai Chengshi replied with a mysterious face:

"Because dry ice can create a low temperature of more than minus 70 degrees, which can be used to preserve influenza virus for a long time."

................................................

the other side.

Takashi Matsuo has accepted the smoke test of the forensics class.

As a result of the test, no gunpowder smoke reaction could be detected on his body.

The police officer of the forensic department who was in charge of checking the pistol also reported that no skin flakes or fingerprints were found on the pistol.

"Ha ha."

"It's been said that I'm not a murderer, so don't wrong good people."

Facing this test result that was absolutely favorable to him, the uneasy Takashi Matsuo felt a little relieved.

Takashi Matsuo taunted the police officers guarding him sternly, while thinking in his heart:

He was wearing gloves when he committed the crime, and there should be no fingerprints on the umbrella.

After killing people, he threw the gloves into the toilet and flushed them away, so they should not be found by the police.

That being the case, then this time...

Even if the Metropolitan Police Department knew that he was the murderer, they might not have enough evidence to convict him.

Well... as long as you don't let the police find out, the way to buy the gun yourself is fine.

If the police can find out this and let the gun dealer identify him, he may not be able to escape.

Takashi Matsuo was relaxed for a while, nervous for a while, just anxiously waiting for the investigation results from Shinichi Hayashi.

And just then...

Lin Xinyi finally came.

But this time the leader is not Lin Xinyi, who is the administrator, nor Mao Lilan, who has just made a big splash.

It was a beauty in men's clothing with a heroic single ponytail.

"Heh... Another replacement came to deal with me?!"

Takashi Matsuo forced disdain on the surface, but at the same time carefully looked at the beautiful girl who took the lead:

Hmm... I can't see the strength, but the appearance is very good.

I have to say that Manager Lin really enjoys it.

The two assistants around him are all young girls who look as good as idol stars.

Takashi Matsuo maliciously speculated about Lin Shinichi's employment intentions in his heart, and then asked with a smile on his face:

"Why, have you found evidence that I am the murderer?"

Naruto Asai, who was leading the reality, did not answer.

He just suddenly asked without thinking:

"Mr. Matsuo."

"Did you accidentally sneeze in that utility room when you shot someone?"

"Eh?" Matsuo Takashi was slightly taken aback.

He didn't know why the other party asked this question, but after he shot and killed someone, he couldn't help but sneezed in the utility room.

Suddenly being told the truth, he immediately looked away a little guilty, and said with a sullen face:

"Say, what do you say..."

"I did go to the utility room, and... I couldn't help sneezing."

"But, that's all today...well, at noon today!"

"At night, especially during the 10 minutes at 3 o'clock, I haven't been to that place at all!"

Takashi Matsuo defended so sternly.

When Asai Chengshi saw his slightly guilty expression, he let out a long sigh of relief:

"It seems that those saliva spots were indeed left by you when you committed the crime."

"In this way, I can rest assured."

"What do you mean..." Matsuo Takashi faintly heard something bad.

Asai Chengshi did not answer in a hurry, but took out a transparent evidence bag.

This is exactly what Mao Lilan took out before, the evidence bag containing the blood-stained mobile phone next to the dead body.

"Look at this phone first..."

"The splattered blood on the phone, everyone can see it, right?"

"Hmm." The onlookers subconsciously nodded.

Asai Chengshi continued to say:

"Mr. Lin taught me that the blood splatter is only formed when the blood in the body is sprayed out due to blood pressure when the deceased was injured during his lifetime."

"The closer the object is to the wound, the denser the splattered blood droplets are distributed."

"And the densely distributed splatter-like blood on the mobile phone shows that..."

"When the deceased was shot in the head, this mobile phone was next to the deceased's head."

"What does that mean?!"

Matsuo Takashi still didn't understand what evidence the other party had found, and his heart became more and more flustered.

"It can be explained that at the moment when the deceased was shot, the mobile phone was next to his head—he was using the mobile phone to make a call!"

Asai Chengshi said unhurriedly:

"In this case, the last call time on the phone is the exact time of his death!"

"So we can be sure that Mr. Suwa was shot and killed from upstairs at around 10:02."

"And just now, Ms. Maori extracted the shooting residue from the window wall of the utility room on the 9th floor, which can detect the reaction of gunpowder smoke."