The Forensic Doctor Better Than a Detective

Chapter 332: Chapter 207: Discoveries from the Second Investigation

”I just saw that there are two basins in the victim’s kitchen.”

”Oh, there are basins in the kitchen?”

Li Jian turned his head and asked, ”Hurry and bring the basins here to compare, see if they are the same.”

Quickly.

Wan ran into the kitchen and brought over the two plastic basins.

Zhang Yean eagerly took out a tape measure and measured the diameter of the two basins, which were 40 centimeters and 60 centimeters respectively.

Then, she bent down to measure the diameter of the mark on the ground, the result was 50 centimeters.

Upon seeing this number, everyone was stunned.

Captain Li immediately asked, ”Are there any other basins in the victim’s house?”

Wan ran back to the kitchen, then searched carefully from the kitchen to the bedroom, and then to the living room.

”No, these should be the only two basins in their house.”

”The only basins?”

”Where did the mark in this place come from then?”

Then, Zhang Yean said in a low voice, ”Mr. Li, should we consider the relevance between this mark and the case?”

”I see a lot of dust around this mark, maybe nothing has been placed here for a long time.”

Li Jian nodded slightly upon hearing this.

However, he did not immediately express his opinion but turned his head to look at Jiang An.

Jiang An analyzed, ”There’s a lot of dust here, but the circular mark formed on the dust is very fresh.”

”This precisely indicates that this mark should have just been formed recently.”

After a long silence, Captain Li asked, ”Jiang An, do you mean this mark is highly relevant to the case?”

Jiang An nodded.

Then, he pointed to the center of the circular mark and said, ”Mr. Li, the tile at the center of this circular mark is slightly yellow, and its color contrast differs from the surrounding tiles.”

”I suspect this place once came into contact with a high-temperature object, which is why it got scorched yellow.”

Upon hearing this, everyone’s eyes widened as they stared straight at Jiang An.

After a while, Captain Li Jian turned his head to the room and nodded lightly.

He said, ”Brother Jiang An, what you said makes sense.”

”The roundish mark appearing at the bedroom entrance is not by chance.”

”Also, the yellowish mark at the center of the circular impression does indeed correspond to the color change we usually see when high-temperature objects touch tiles.”

”Moreover, since both deceased individuals were found to be poisoned with carbon monoxide, this place is highly likely to be the source of carbon monoxide emission from the burning.”

After saying this, Captain Li’s expression turned exceptionally serious.

Initially, he believed it was an accidental death case.

Previously, he even thought that re-investigating the scene was meaningless.

Yet, in less than an hour, the murder case was clarified.

This involved the loss of two lives, and the pressure attacked like a looming mountain.

Li Jian licked his dry lips, took out his phone, and walked out of the room.

He walked all the way to the stairway corner, where the phone screen’s light illuminated the dim stairwell.

Captain Li dialed Mr. Ma’s number.

”Hello?”

”What, is there a new development over there?”

Li Jian nodded and replied, ”Report to Mr. Ma, we indeed have a new discovery here.”

”Has the cause of death been identified?”

”Not yet, but there is something more troublesome than the cause of death now.”

”Oh? What’s the matter?”

Mr. Ma was puzzled, completely unable to understand Captain Li’s meaning.

Captain Li slowly said, ”Just now, during our re-examination of the scene, we found a circular mark in the victim’s bedroom.”

”Moreover, there is a light yellow high-temperature burn mark in the center of this circular impression.”

”From the current situation, we suspect the murderer might have brought a carbon monoxide device inside to burn and generate carbon monoxide.”

”Releasing carbon monoxide?”

Mr. Ma didn’t understand for a moment.

Having been engaged in criminal investigation for so many years, he was hearing about such a modus operandi for the first time.

After a while, Mr. Ma asked, ”Does anyone really bring a carbon monoxide device inside to burn and produce carbon monoxide?”

Li Jian replied, ”Mr. Ma, this is our current speculation.”

The other end of the line fell silent again.

Mr. Ma had never encountered such a case.

At this moment, he was more concerned not with the case itself but with the significant work pressure behind it.

From a case initially considered accidental death, it suddenly turned into a case of two victims being killed simultaneously, which is not something explained by just a couple of sentences.

As the deputy director responsible for criminal investigations at the police bureau, the pressure he endured could be imagined.

Finally, he spoke in a deep voice, ”Li Jian, this case must be handled firmly; investigate carefully at the scene, I’ll be over immediately.”

”Yes, Mr. Ma, we will conduct a thorough and detailed investigation, not missing any clues.”

After hanging up the phone, Li Jian returned to the scene again.

At this time, Jiang An, Zhang Yean, Wan, and others were still in the victim’s bedroom, taking photos and extracting the mark.

Seeing Li Jian come inside, Jiang An stepped forward and said, ”Mr. Li, if it is confirmed that this is the source of carbon monoxide poisoning, then it is undoubtedly a murder case.”

Li Jian nodded, with a heavy expression.

”Mr. Li, when you initially surveyed the scene, did you find any signs of doors or windows being broken?”

Li Jian recalled and said, ”All the doors and windows here are intact, with no signs of anyone breaking in.”

”Also, during our first survey of the scene, not only did we examine the door lock’s cylinder, but we also checked the windows and window sills, and found no signs of climbing, nor were the doors forcibly opened.”

Upon hearing this, Jiang An stood in place, lost in deep thought.

”If the carbon monoxide-generating device was brought in by the murderer, how did they enter the scene?”

Upon hearing this question, Wan and Zhang Yean also showed puzzled expressions.

”That’s odd, surely it wasn’t through lock-picking technology, right?”

Li Jian nodded and said, ”Initially, we studied this room’s door lock carefully and found no lock-pick gear marks inside the cylinder, nor was the door lock damaged in any way.”

Wan suddenly said, ”I wonder, did the murderer have the victim’s house key and just opened the door to spread poison?”

Zhang Yean pursed her lips and said, ”I feel that’s unlikely.”

”Holding someone else’s key, opening someone else’s door, and then killing that person—what kind of bizarre operation is that? It defies logic.”

While the two were discussing, both Jiang An and Li Jian were deep in thought.

Five minutes later, Jiang An asked, ”Mr. Li, who was the last person to bring the two victims home?”

Li Jian answered, ”According to the initial investigation, it was two friends who had dinner with them that evening.”

”Male or female?”

”I remember both were male friends because they felt the male victim drank a bit too much, so they brought them home.”

Jiang An nodded and asked again, ”Have they been thoroughly investigated?”

”No.”

”At the time we believed it was alcohol poisoning, so many peripheral investigation tasks were not conducted with sensitive standards.”

Then, Li Jian continued, ”But now, it seems the case is no longer a mere accidental death but a murder case.”

”So, the subsequent investigations must be conducted according to standards for murder cases.”

”We’ll summon those two individuals immediately for further investigation at the police station.”

A moment later, Jiang An said, ”If the murderer neither climbed over the wall nor broke or picked the lock to enter the scene.”

”Then it fully indicates the murderer had a key, but how did they obtain it?”

Subsequently, he asked, ”Mr. Li, are the keys to the victim’s home still there?”

”Yes, during our first survey of the scene, we found two sets of keys hanging on the shoe cabinet at the entrance.”

”One set of keys is still on the shoe cabinet, and the other set has been seized by the police station as evidence, to facilitate subsequent investigations and door unlocking.”

Jiang An walked over to the shoe cabinet.

He wore white latex gloves, picked up the keys, and began to examine them closely.

He looked for a long time but didn’t find anything unusual.

However, just as he was about to put the keys back on the shoe cabinet, a glimpse of black powder-like material on his glove caught his eye.

Instantly, Jiang An’s focus locked tightly on that set of keys.