The most important thing in detecting a poisoning case is to determine where the source of the poison comes from. Basically, once the source of the poison is determined, the nature of the poisoning case can be determined.

There are only three types of poisoning cases. The first is poisoning by oneself, the second is accidental poisoning, and the third is poisoning by others.

Strictly speaking, the first situation is self-harm, the second situation is an accident, and only the third situation is a criminal case. Therefore, the police must exclude the first two situations before they can conduct a criminal investigation.

After confirming that the deceased was poisoned, Huang Qifai immediately looked for the source of the poison. This idea of ​​handling the case was also correct.

Forensics immediately began to examine the food and drinks remaining on the table. Huang Qifai continued to question the deceased's friends.

"Have you noticed whether the deceased has any unusual behavior recently?" Huang Qifai asked.

Everyone shook their heads, and Huang Qifa continued to remind: "If you think about it carefully, it means that there has been a change in mood, such as becoming irritable, uneasy, panicked, nervous, etc."

Huang Qifai wanted to know if the deceased had any tendency to commit suicide. After all, people in Xiangjiang live under a lot of pressure, and many people have mental problems. It is not a new thing for them to commit suicide suddenly because they can't think of anything.

Teaching assistant Xue Youlin immediately said: "Sir, is it because of too much academic pressure? As far as I know, Yu Zhenghuang is currently writing his graduation thesis, but it seems that the writing of the thesis is not going well."

"Why didn't it go well?" Huang Qifai asked immediately.

"I'm not sure about the specifics. I'm just a teaching assistant, not qualified enough to guide graduate students in writing thesis. Moreover, the thesis is a personal research result, so I can't ask too detailed questions."

Xue Youlin paused for a moment, then continued: "Actually, it is common in school to have trouble writing a thesis. Many students are worried about their graduation thesis. When I was getting my degree, I also worried about the thesis every day.

!”

Huang Qifai nodded and then asked: "According to your understanding, did the deceased Yu Zhenghuang have any enmity with anyone?"

"I'm not sure about this. Lin Zhijian may know that the two of them have classes together every day." Assistant teacher Xue Youlin replied.

Lin Zhijian hurriedly stepped forward: "Sir, Yu Zhenghuang probably doesn't have any enemies. He and I have the same tutor and we study together every day. I haven't heard that he has any enemies.

Moreover, we are still students, we have not entered the society, and we do not have too complicated interpersonal relationships. We usually live between home and school, and it is impossible to offend any enemies."

"What about the family situation of the deceased? Did he owe huge debts?" Huang Qifa asked next.

"I know a little bit about this. His family background is neither good nor bad. His parents are ordinary office workers. I can't remember exactly what they do. But I haven't heard that he has any debts.

situation." Lin Zhijian answered.

"That is to say, the family is harmonious and both parents are still alive." Huang Qifa then asked: "Did the deceased have any emotional disputes?"

"He is single, and it has been almost half a year since he broke up with his ex-girlfriend! I don't know who dumped whom, but he has not seen his ex-girlfriend pester him in the past six months, and he has not mentioned anything about his girlfriend in advance. It should be

It's easy to get together and part ways." Lin Zhijian replied.

Huang Qifai asked these questions to determine how likely the deceased was to commit suicide.

Depression, broken love, debt collection and revenge, etc., are all causes of suicide, so Huang Qifai also focused on asking questions in this area.

Next to him, He Jiahui really couldn't stand it anymore. Huang Qiqi asked for a long time, but he didn't mention the core question.

So He Jiahui directly asked the forensic evidence: "Were any containers containing cyanide found on the deceased's body?"

This forensic evidence was the same one used in the murder case in the police academy cafeteria last time. He turned around and took a look and thought to himself, isn't this the trainee police officer who solved the case in the police academy!

Looking at the police officer ID card on He Jiahui's chest again, I realized that he had graduated and was now an official police officer.

Since the other party was an official police officer, there was no doubt about revealing the facts of the case, so the forensic officer said: "No container for storing cyanide was found on the deceased."

"Did you find anything on the ground nearby, in the corners, or in the cracks of the sofa?" He Jiahui then asked.

"No, I've checked all the corners and gaps on the sofa, and there's nothing suspicious." The forensic officer replied.

He Jiahui nodded, turned to Huang Qifai and said: "Then it can be concluded with a high probability that the deceased did not commit suicide!"

"How do you know it wasn't suicide!" Huang Qifai asked.

"If the deceased committed suicide, then why couldn't he find a container for storing cyanide? He couldn't conjure cyanide out of thin air!" He Jiahui replied.

"Maybe the deceased threw away the container!" Huang Qifai argued.

"Where to throw it? You must know that after taking cyanide, an attack will occur in two minutes. If the container storing cyanide is thrown away, it will not be far away. But it was not found nearby."

He Jiahui paused and then said: "Besides, if the deceased carried poison with him and planned to commit suicide by taking it, how could he bother to hide the poison?"

Huang Qifai was speechless, but he had to admit that the deceased did not commit suicide by taking poison.

"Since it's not suicide, it's very likely that he killed him." Huang Qifai looked at the deceased's friends and asked, "Has any of you left before? For example, to go to the bathroom or something."

Everyone looked at me and me, and shook their heads, indicating that they had not left.

At this time, the forensic side also provided the results.

Just listen to the forensic introduction: "I have tested the food on the table, leftover birthday cakes, durian cakes, butter cakes, egg tarts, potato chips, fruits, and no toxic reactions were found in any food.

In addition, I have also tested the plastic knives for cutting cakes, the boxes for durian cakes, butter cakes and egg tarts, and the plates for potato chips and fruits, and no toxic reactions were found.

Finally, I tested the beers on the table, and only the can of beer in front of the deceased found cyanide reaction, but no toxic reaction was found in the other beers."

"In other words, the source of the poison is the can of beer that the deceased drank!" Huang Qifai asked fiercely: "Where did this bottle of poisonous beer come from?"

"We ordered the wine and the waiter brought it to us." Someone immediately replied.

"Where's the waiter responsible for serving wine to this table? Find him quickly."

Huang Qifai gave the order and the waiter was immediately called over.

"Sir, I'm sorry, I didn't poison you!" the waiter explained miserably.

"Don't be nervous, I didn't say you poisoned me." Huang Qifai continued: "I want you to carefully recall the process of serving wine to this table. All details must be explained clearly. Don't make any mistakes.

It’s also good for you to hide it.”

The waiter thought for a while and replied: "There were seven people at this table, and they also ordered seven cans of beer. Then I went to get the beer, put it in an ice bucket and carried it over. When I took it, the beer cans were still there.

It’s not open!”

"Have you met anyone or anything in the meantime? Has the beer ever left your sight?" Huang Qifai then asked.

"The beer has been chilled. If the ice cubes melt, the taste will be bad. So I didn't delay after getting the beer. I delivered it directly without stopping in the middle. The ice bucket was always in my hand and never left my side.

Sight." The waiter replied.

"Okay, let's continue. What happens after you deliver the wine?" Huang Qifai continued.

"I put the ice bucket on the table and said, the beer you ordered has arrived, and then they took the beer from the ice bucket themselves. They also opened the beer cans themselves. After delivering the beer, I left

Yes." The waiter replied.

"In other words, they took the beer themselves, instead of you delivering it to everyone?" Huang Qifai continued to ask.

"That's right, they took it themselves. I didn't touch it during the whole process." The waiter nodded.
Chapter completed!